Disc Brake System Chevrolet Chevy Express G3500

Fastener Tightening Specifications

Fastener Tightening Specifications

Disc Brake Component Specifications

Disc Brake Component Specifications

Diagnostic Starting Point - Disc Brakes

Begin the disc brake system diagnosis with Diagnostic Starting Point - Hydraulic Brakes in Hydraulic Brakes. The use of the Diagnostic Starting Point will lead to the identification of the correct procedure for diagnosing the system and where the procedure is located.

Brake Rotor Thickness Measurement

1. Clean the brake pad lining contact surface of the brake rotor with denatured alcohol or an equivalent brake cleaner.
2. Using a calibrated micrometer measure and record the lowest thickness of the brake rotor at 4 or more points equally spaced around the rotor. Ensure that the measurements are only taken within the brake pad lining contact area and that the micrometer is positioned the same distance from the outside edge of the rotor for each measurement.
3. Compare the lowest thickness measurement recorded to the following specifications: Specification - Front Brake JH5: Brake rotor minimum allowable thickness after refinishing 28.0 mm (1.102 in) Brake rotor discard thickness 27.50 mm (1.083 in) Specification - Front Brake JH6/JH7: Brake rotor minimum allowable thickness after refinishing 37.0 mm (1.457 in) Brake rotor discard thickness 36.50 mm (1.437 in) Specification - Rear Brake JH5: Brake rotor minimum allowable thickness after refinishing 29.0 mm (1.142 in) Brake rotor discard thickness 28.50 mm (1.122 in) Specification - Rear Brake JH6/JH7: Brake rotor minimum allowable thickness after refinishing 28.0 mm (1.102 in) Brake rotor discard thickness 27.50 mm (1.083 in)
4. If the lowest thickness measurement of the brake rotor is above the minimum allowable thickness after refinishing specification then the rotor may be refinished, depending upon surface and wear conditions which may be present.
5. If the lowest thickness measurement of the brake rotor is at or below the minimum allowable thickness after refinishing specification then the rotor may not be refinished.
6. If the lowest thickness measurement of the brake rotor is at or below the discard thickness specification then the rotor requires replacement.

Brake Rotor Thickness Variation Measurement

1. If the inboard friction surface of the brake rotor is not accessible, reposition and support the caliper with the brake pads. Refer to «Brake Pads Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) and/or «Brake Pads Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.
3. Using a micrometer calibrated in thousanths-of-a-millimeter, or ten-thousanths-of-an-inch, measure and record the thickness of the brake rotor at four or more points, evenly spaced around the rotor. Ensure that the measurements are only taken within the friction surfaces and that the micrometer is positioned the same distance from the outer edge of the rotor, about 13 mm (1/2 in), for each measurement.
4. Calculate the difference between the highest and lowest thickness measurements recorded to obtain the amount of thickness variation.
5. Compare the thickness variation measurement to the following specification: Specification: Brake rotor maximum allowable thickness variation: 0.025 mm (0.001 in)
6. If the brake rotor thickness variation measurement exceeds the specification, the rotor requires refinishing or replacement.

Brake Rotor Surface and Wear Inspection

Tools Required: J 8001 Dial Indicator set, or equivalent. See Special Tools and Equipment .

1. With the tire and wheel assemblies removed and the brake rotors retained by wheel lug nuts, clean the braking/friction surfaces of the brake rotor with denatured alcohol or an equivalent approved brake cleaner.
2. Inspect the braking surfaces of the brake rotor for the following braking surface conditions: Heavy rust and/or pitting Light surface rust can be removed with an abrasive disc; heavy surface rust and/or pitting must be removed by refinishing the rotor. Cracks and/or heat spots Excessive blueing discoloration
3. If the braking surfaces of the brake rotor exhibits one or more of the braking surface conditions, the rotor requires refinishing or replacement.
4. Using a calibrated micrometer measure and record the thickness variation of the brake rotor at 4 or more points around the brake rotor. Ensure that the measurements are only taken within the brake pad lining contact area and that the micrometer is positioned the same distance from the outside edge of the rotor for each measurement.
5. Compare the thickness variation recorded to the following specification: Specification: Brake rotor maximum allowable thickness variation 0.025 mm (0.001 in).
6. If the brake rotor thickness variation exceeds the specification, the rotor requires refinishing or replacement.
7. Using the micrometer measure and record any grooves present on the rotor braking surface.
8. Compare the groove/scoring depth recorded to the following specification: Specification: Brake rotor maximum allowable scoring 1.50 mm (0.059 in).
9. If the brake rotor scoring depth exceeds the specification, or if an excessive amount of scoring is present, the rotor requires refinishing or replacement.
10. Mount a dial indicator J 8001 or equivalent, and position the indicator button so it contacts the brake rotor at a 90 degree angle, approximately 13 mm (0.5 in) from the rotor's outer edge. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
11. Measure and record the lateral runout of the brake rotor. Rotate the rotor until the lowest reading is displayed on the indicator dial and zero the dial. Rotate the rotor until the highest reading is displayed on the dial. Measure and record the amount of lateral runout.
12. Compare the lateral runout of the brake rotor to the following specification: Specification: Brake rotor maximum allowable lateral runout 0.05 mm (0.002 in).
13. If the brake rotor lateral runout exceeds the specification the rotor requires refinishing or replacement.

Brake Rotor Assembled Lateral Runout (LRO) Measurement

Tools Required

1. J 39544-KIT Torque-Limiting Socket Set, or equivalent. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. J 41013 Rotor Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. J 42450-A Wheel Hub Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
4. J 45101 Hub and Wheel Runout Gage. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
5. J 45101-100 Conical Brake Rotor Washers. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

1. Matchmark the position of the brake rotor to the wheel studs if this has not been done already.
2. Inspect the mating surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles, corrosion, rust, or debris remaining. If the wheel hub/axle flange and/or if the brake rotor mating surfaces exhibit these conditions, perform the following steps: Remove the brake rotor from the vehicle. Refer to «Brake Rotor Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) and/or «Brake Rotor Replacement - Rear (W/Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-wdual) or «Brake Rotor Replacement - Rear (Except Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-except) . Using the J 42450-A , thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Using the J 41013 , thoroughly clean any rust or corrosion from the mating surface of the brake rotor. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.
3. Install the rotor to the hub/axle flange using the matchmark made prior to removal.
4. Hold the rotor firmly in place against the hub/axle flange and install one of the J 45101-100 (1), and one lug nut (2) onto the upper-most wheel stud. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
5. Continue to hold the rotor secure and tighten the lug nut firmly by hand.
6. Install the remaining J 45101-100 and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
7. Using the J 39544-KIT , or equivalent, tighten the lug nuts in a star-pattern to specification, in order to properly secure the rotor. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
8. If the brake rotor has been REFINISHED or REPLACED with a new rotor, proceed to step 14.
9. If the brake rotor meets the following criteria, proceed to step 10. The rotor is within specifications and is being REUSED The rotor has NOT been refinished The rotor does NOT exhibit thickness variation exceeding the maximum allowable level
10. Mount a dial indicator, J 45101 , or equivalent, to the steering knuckle and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .5 in) from the outer edge of the rotor.
11. Measure and record the assembled LRO of the brake rotor. Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero. Rotate the rotor until the highest reading is displayed on the dial. Mark the location of the high spot relative to the nearest wheel stud, or studs. Measure and record the amount of LRO.
12. Compare the brake rotor assembled LRO to the following specification: Specification: Front brake rotor maximum allowable assembled lateral runout: 0.13 mm (0.005 in) Rear brake rotor maximum allowable assembled lateral runout: 0.13 mm (0.005 in)
13. If the brake rotor assembled LRO is within specifications, proceed to step 18. If the brake rotor assembled LRO exceeds the specification, refinish the rotor to ensure true parallelism, refer to «Brake Rotor Refinishing»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-refinishing) . After refinishing the rotor, proceed to step 14.
14. Mount a dial indicator, J 45101 , or equivalent, to the steering knuckle and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
15. Measure and record the assembled LRO of the brake rotor. Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero. Rotate the rotor until the highest reading is displayed on the dial. Mark the location of the high spot relative to the nearest wheel stud, or studs. Measure and record the amount of LRO.
16. Compare the brake rotor assembled LRO to the following specification: Specification: Front brake rotor maximum allowable assembled lateral runout: 0.13 mm (0.005 in) Rear brake rotor maximum allowable assembled lateral runout: 0.13 mm (0.005 in)
17. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Correction»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
18. If the brake rotor assembled LRO measurement is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the J 45101-100 and the lug nuts. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Brake Pad Inspection

1. Inspect the disc brake pads at regular intervals, or whenever the tire and wheel assemblies are removed from the vehicle.
2. If replacement is necessary, always replace disc brake pads in axle sets.
3. Inspect both edges of the disc brake pad friction surfaces (3). The highest rate of wear normally occurs at the trailing edge of the disc brake pads.
4. Inspect the thickness of the disc brake pads (3) in order to ensure that they have not worn prematurely. The disc brake pad wear should be approximately even per axle set.
5. Both front and rear disc brake pads have integral, audible wear sensors (1). When the disc brake pad wear reaches the minimum allowable thickness, the wear sensor contacts the disc brake rotor (2). The wear indicator will then produce an audible, high-pitched warning noise during wheel rotation.
6. Replace the disc brake pads when the friction surface (3) is worn to within 0.76 mm (0.030 in) of the mounting plates.
7. Remove the brake calipers and inspect the friction surfaces of the inner and outer disc brake pads to ensure that they are level. Place the disc brake pad friction surfaces together and measure the gap between the surfaces. If more than 0.13 mm (0.005 in) gap exists midway between the length of the disc brake pads, replace the disc brake pads.
8. Verify that any disc brake pad shims that may be required are in place and not damaged or excessively corroded. Replace any missing or damaged shims in order to preserve proper disc brake performance.
9. Replace the disc brake pads if any have separated from the mounting plates.
10. Inspect the disc brake pads friction surfaces for cracks, fractures, or damage which may cause noise or otherwise impair disc brake performance.

Scheme 13

1. Inspect the brake caliper housing (1) for cracks, excess wear, and/or damage. If any of these conditions are present, the brake caliper requires replacement.
2. Inspect the caliper piston dust boot seal (2) for cracks, tears, cuts, deterioration and/or improper seating in the caliper body. If any of these conditions are present, the brake caliper requires overhaul or replacement.
3. Inspect for brake fluid leakage around the caliper piston dust boot seal (2) and on the disc brake pads. If there is any evidence of brake fluid leakage, the brake caliper requires overhaul or replacement.
4. Inspect for smooth and complete travel of the caliper piston, or pistons, into the caliper bore, or bores: The movement of a caliper piston into a caliper bore should be smooth and even. If a caliper piston is frozen or difficult to bottom, the caliper requires overhaul or replacement. For single piston caliper applications, insert a discarded inner brake pad (2) or block of wood in front of the piston. Using a large C-clamp (1) installed over the body of the caliper (3) and against the brake pad or block of wood, slowly bottom the piston in the bore. For dual piston caliper applications, insert a discarded inner brake pad (2) or block of wood in front of the pistons. Using 2 large C-clamps (1) installed over the body of the caliper (3) and against the brake pad or block of wood, slowly bottom the pistons evenly into the bores.

Disc Brake Mounting and Hardware Inspection - Front

Scheme 14

1. Inspect the fluid level in the brake master cylinder reservoir.
2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level then no brake fluid needs to be removed from the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level then remove brake fluid to the midway point before proceeding.
4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
5. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Grasp the brake caliper housing and try to move the brake caliper housing up/down and forward/reverse in relation to the brake caliper mounting bracket. If excessive looseness is observed the brake caliper bracket bushings and/or the brake caliper mounting bolts may need to be replaced.
7. Compress the front caliper pistons. Install a large C-clamp over the top of the caliper housing and against the back of the outboard pad. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores. Remove the C-clamp from the caliper.
8. With the pistons compressed into the caliper bores, grasp the brake caliper housing and slide it back and forth on the brake caliper mounting bolts. Check for smooth operation. If the brake caliper housing slide force is high or the brake caliper housing does not slide smoothly, inspect the brake caliper mounting bolts and/or the brake caliper mounting bracket bushings for wear or damage. If wear or damage conditions are found, replacement of the brake caliper mounting bolts and/or the brake caliper mounting bracket bushings is necessary.
9. Remove the brake caliper mounting bolts from the brake caliper mounting bracket and support the brake caliper using heavy mechanics wire. Do Not remove the hydraulic brake hose from the caliper. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
10. Remove the disc brake pads from the brake caliper mounting bracket.
11. Inspect the disc brake pad mounting hardware for the following: Missing mounting hardware Excessive corrosion Bent mounting tabs Looseness at the brake caliper mounting bracket Looseness at the disc brake pads Excessive contaminants in the brake caliper mounting bracket surface and threads.
12. If any of the conditions listed are found, the disc brake pad mounting hardware requires replacement.
13. Ensure the disc brake pads are held firmly in place on the brake caliper mounting bracket, yet slide easily on the mounting hardware without binding.
14. Inspect the caliper bolts (1) for the following: Binding Seizing Looseness in the brake caliper mounting bracket (3) Bent or damaged brake caliper mounting bolts Cracked or torn boots (4) Missing boots Bent or damaged brake caliper mounting bracket (3)
15. If any of the conditions listed are found then the brake caliper mounting hardware requires replacement.
16. Install the disc brake pads to the brake caliper mounting bracket.
17. Install the disc brake caliper to the brake caliper mounting bracket. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Disc Brake Mounting and Hardware Inspection - Rear

1. Inspect the fluid level in the brake master cylinder reservoir.
2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level then no brake fluid needs to be removed from the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level then remove brake fluid to the midway point before proceeding.
4. Raise and support the vehicle. Refer «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) to in General Information.
5. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Grasp the brake caliper housing and try to move the brake caliper housing up/down and forward/reverse in relation to the brake caliper mounting bracket. If excessive looseness is observed the brake caliper bracket bushings and/or the brake caliper mounting bolts may need to be replaced.
7. Compress the rear brake caliper pistons. Install a large C-clamp over the top of the caliper housing and against the back of the outboard pad. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores. Remove the C-clamp from the caliper.
8. With the pistons compressed into the caliper bores, grasp the brake caliper housing and slide it back and forth on the brake caliper mounting bolts. Check for smooth operation. If the brake caliper housing slide force is high or the brake caliper housing does not slide smoothly, inspect the brake caliper mounting bolts and/or the brake caliper mounting bracket bushings for wear or damage. If wear or damage conditions are found, replacement of the brake caliper mounting bolts and/or the brake caliper mounting bracket bushings is necessary.
9. Remove the brake caliper mounting bolts from the brake caliper mounting bracket and support the brake caliper using heavy mechanics wire. Do Not remove the hydraulic brake hose from the caliper. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) in Disc Brakes.
10. Remove the disc brake pads from the brake caliper mounting bracket.
11. Inspect the disc brake pad mounting hardware for the following: Missing mounting hardware Excessive corrosion Bent mounting tabs Looseness at the brake caliper mounting bracket Looseness at the disc brake pads Excessive contaminants in the brake caliper mounting bracket surface and threads.
12. If any of the conditions listed are found, the disc brake pad mounting hardware requires replacement.
13. Ensure the disc brake pads are held firmly in place on the brake caliper mounting bracket, yet slide easily on the mounting hardware without binding.
14. Inspect the caliper bolts (1) for the following: Binding Seizing Looseness in the brake caliper mounting bracket (3) Bent or damaged brake caliper mounting bolts Cracked or torn boots (4) Missing boots Bent or damaged brake caliper mounting bracket (3)
15. If any of the conditions listed are found then the brake caliper mounting hardware requires replacement.
16. Install the disc brake pads to the brake caliper mounting bracket.
17. Install the disc brake caliper to the brake caliper mounting bracket. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) in Disc Brakes.

Removal Procedure

1. Inspect the fluid level in the brake master cylinder reservoir.
2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed from the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding.
4. Raise and support the vehicle. Refer to in «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
5. Remove the tire and wheel assembly. Refer to in «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Inspect the caliper operation. Refer to «Brake Caliper Inspection»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
7. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
8. Remove the brake pads from the caliper mounting bracket.
9. Remove and discard the anti-rattle clips from the brake caliper mounting bracket.
10. Inspect the caliper and mounting bracket. Refer to «Brake Caliper Inspection»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Installation Procedure

1. Install new anti-rattle clips to the inside ends of the caliper mounting bracket.
2. Install the brake pads to the caliper mounting bracket.
3. Place the new pads in the same orientation as noted during removal.
4. Install the brake caliper. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
5. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Remove the safety stands.
7. Lower the vehicle.
8. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.
9. Slowly release the brake pedal.
10. Wait 15 seconds, then repeat steps 7-8 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
11. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.
12. Burnish the brake pads and rotors. Refer to «Burnishing Pads and Rotors»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__burnishing-pads-and-rotors) .

Note. Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Cautions and Notices.

1. Inspect the fluid level in the brake master cylinder reservoir.
2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed from the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding.
4. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
5. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Inspect the caliper operation. Refer to «Brake Caliper Inspection»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
7. Place a C-clamp as shown. Slowly bottom the pistons of the caliper. It may be necessary to reposition the C-clamp to allow both of the pistons to bottom into the caliper bores.
8. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
9. Inspect the caliper assembly. Refer to «Brake Caliper Inspection»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
10. Remove the brake pads from the brake caliper bracket. Note the orientation.
11. Remove and discard the anti-rattle clips from the brake caliper mounting bracket.

1. Install the anti-rattle clips to the brake caliper bracket.
2. Install the brake caliper. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. Install the brake pads to the brake caliper bracket. Place the new pads in the same orientation as noted during removal.
4. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
5. Lower the vehicle.
6. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.
7. Slowly release the brake pedal.
8. Wait 15 seconds, then repeat steps 7-8 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
9. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.
10. Burnish the brakes pads and rotors as necessary. Refer to «Burnishing Pads and Rotors»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__burnishing-pads-and-rotors) .

Burnishing Pads and Rotors

Burnishing the brake pads and brake rotors is necessary in order to ensure that the braking surfaces are properly prepared after service has been performed on the disc brake system.

This procedure should be performed whenever the disc brake rotors have been refinished or replaced, and/or whenever the disc brake pads have been replaced.

1. Select a smooth road with little or no traffic.
2. Accelerate the vehicle to 48 km/h (30 mph). IMPORTANT: Use care to avoid overheating the brakes while performing this step.
3. Using moderate to firm pressure, apply the brakes to bring the vehicle to a stop. Do not allow the brakes to lock.
4. Repeat steps 2 and 3 until approximately 20 stops have been completed. Allow sufficient cooling periods between stops in order to properly burnish the brake pads and rotors.

Scheme 15

1. Inspect the fluid level in the brake master cylinder reservoir.
2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed from the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding.
4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
5. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Compress the brake caliper pistons. Install a large C-clamp over the top of the caliper housing and against the back of the outboard pad. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores. Remove the C-clamp from the caliper.
7. Clean all dirt and foreign material from the brake hose end.
8. Remove the brake hose to caliper bolt from the brake caliper.
9. Remove and discard the 2 copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake hose end.
10. Remove the brake hose from the caliper.
11. Remove the 2 brake caliper mounting bolts.
12. Remove the brake caliper from the brake caliper mounting bracket.

1. Install the brake caliper to the brake caliper mounting bracket.
2. Perform the following procedure before installing the caliper mounting bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
3. Install the 2 brake caliper mounting bolts. Tighten: Tighten the bolts to 108 N.m (80 lb ft).
4. Remove the rubber cap or plug from the exposed brake hose fitting end.
5. Assemble the 2 new copper brake hose gaskets and the brake hose to caliper bolt to the brake hose.
6. Install the brake hose to caliper bolt to the brake caliper. Tighten: Tighten the brake hose to caliper bolt to 44 N.m (32 lb ft).
7. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system) in Hydraulic Brakes.
8. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
9. Lower the vehicle.
10. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.

Scheme 16

1. Inspect the fluid level in the brake master cylinder reservoir.
2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level then no brake fluid needs to be removed from the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level then remove brake fluid to the midway point before proceeding.
4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
5. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
6. Compress the brake caliper pistons. Install a large C-clamp over the top of the caliper housing and against the back of the outboard pad. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores. Remove the C-clamp from the caliper.
7. Clean all dirt and foreign material from the brake hose end.
8. Remove the brake hose to caliper bolt from the brake caliper.
9. Remove and discard the 2 copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake hose end.
10. Remove the caliper guide pin bolts.
11. Remove the brake caliper from the vehicle.
12. Inspect the caliper assembly. Refer to «Brake Caliper Inspection»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

1. If you are installing new brake pads use a C-clamp in order to compress the pistons to the bottom of the caliper bores. Use the old brake pad, a metal plate or a wooden block across the face of the pistons in order to protect the pistons and the caliper boots.
2. Ensure that the caliper boots are below the level of the face of both pistons.
3. Install the brake caliper to the brake caliper mounting bracket.
4. Perform the following procedure before installing the caliper guide pin bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
5. Install the brake caliper mounting bolts.
6. Tighten the brake caliper guide pin bolts - rear. Tighten: Tighten the bolts to 42 N.m (31 lb ft) (15 Series). Tighten the bolts to 108 N.m (80 lb ft) (25/35 Series).
7. Remove the rubber cap or plug from the exposed brake hose fitting end.
8. Assemble the 2 NEW copper brake hose gaskets and the brake hose to caliper bolt to the brake hose.
9. Connect the brake hose at the caliper by installing the brake hose to caliper bolt. Tighten: Tighten the brake hose to caliper bolt to 40 N.m (30 lb ft).
10. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system) in Antilock Brake System.
11. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
12. Lower the vehicle.
13. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.

Brake Caliper Overhaul - Front

Disassembly Procedure

1. Remove the brake caliper from the vehicle. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Place a thin piece of wood in front of the piston in order to prevent damage. Remove the piston by directing compressed air into the brake hose inlet fitting port of the brake caliper housing.
3. Remove the piston boot.
4. Remove the piston seal.
5. Remove the brake caliper bleed screw cap.
6. Remove the brake caliper bleed screw.
7. Inspect the brake caliper bore and the piston seal groove for scoring and corrosion. If you find excessive scoring or corrosion around the piston seal area, replace the brake caliper housing.
8. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and replace the brake caliper mounting bracket if necessary.
9. Clean all of the residue from the brake pad guiding surfaces on the brake caliper housing and the brake caliper mounting bracket.
10. Clean all of the parts not included in the repair kit with denatured alcohol.
11. Dry all of the parts with filtered unlubricated compressed air.
12. Blow out all passages in the brake caliper housing and the brake caliper bleeder valve.

Assembly Procedure

1. Install the brake caliper bleed screw.
2. Install the brake caliper bleed screw cap.
3. Lubricate the new piston seals and the brake caliper bore seal grooves with brake fluid, GM P/N 12388967 (Canadian P/N 992667).
4. Install new seals into the brake caliper bore seal grooves.
5. Ensure that the seals are not twisted.
6. Lubricate the brake caliper bores and the pistons with brake fluid, GM P/N 12388967 (Canadian P/N 992667).
7. Install the boot and piston. Install the boot over the end of the piston so that the fold will face toward the brake caliper housing piston bore opening. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore. Push down the piston to the bottom of the brake caliper bore. Ensure the boot seats properly into the piston groove and into the groove in the brake caliper bore. Repeat step 7 for the remaining piston.
8. Install the brake caliper to the vehicle. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Brake Caliper Overhaul - Rear (15 Series)

1. Remove the brake caliper from the vehicle. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Place a thin piece wood in front of the piston in order to prevent damage. Remove the piston by directing compressed air into the brake hose inlet fitting port of the brake caliper housing.
3. Remove the piston boot.
4. Remove the piston seal.
5. Remove the brake caliper bleed screw cap.
6. Remove the brake caliper bleed screw.
7. Inspect the brake caliper bore and the piston seal groove for scoring and corrosion. If you find excessive scoring or corrosion around the piston seal area, replace the brake caliper housing.
8. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and replace the brake caliper mounting bracket if needed.
9. Clean all of the residue from the brake pad guiding surfaces on the brake caliper housing and the brake caliper mounting bracket.
10. Clean all of the parts not included in the repair kit with denatured alcohol.
11. Dry all the parts with non lubricated filtered compressed air.
12. Blow out all passages in the brake caliper housing and the brake caliper bleeder valve.

1. Install the brake caliper bleed screw. Tighten: Tighten the brake caliper bleed screw to 12 N.m (106 lb in).
2. Install the brake caliper bleed screw cap.
3. Lubricate the new piston seal and the brake caliper bore seal groove with brake fluid.
4. Install the new seal into the brake caliper bore seal groove.
5. Ensure that the seal is not twisted.
6. Lubricate the brake caliper bore and the piston with brake fluid.
7. Install the boot and piston. Install the boot over the end of the piston so that the fold will face toward the brake caliper housing piston bore opening. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore. Push down the piston to the bottom of the brake caliper bore. Ensure that the boot is properly seats into the piston groove and into the groove in the brake caliper bore.
8. Install the brake caliper to the vehicle. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Brake Caliper Overhaul - Rear (25/35 Series)

Scheme 17

1. Remove the brake caliper from the vehicle. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Place a thin piece wood in front of the pistons in order to prevent damage. Remove the pistons by directing compressed air into the brake hose inlet fitting port of the brake caliper housing.
3. Remove the 2 pistons.
4. Remove the 2 piston boots.
5. Remove the 2 piston seals.
6. Remove the brake caliper bleed screw cap.
7. Remove the brake caliper bleed screw.
8. Inspect the brake caliper bores and the piston seal grooves for scoring and corrosion. If you find excessive scoring or corrosion around the 2 piston seal areas replace the brake caliper housing.
9. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and replace the brake caliper mounting bracket if needed.
10. Clean all the residue from the brake pad guiding surfaces on the brake caliper housing and the brake caliper mounting bracket.
11. Clean all the parts not included in the repair kit with denatured alcohol.
12. Dry all the parts with non lubricated filtered compressed air.
13. Blow out all passages in the brake caliper housing and the brake caliper bleeder valve.

1. Install the brake caliper bleed screw. Tighten: Tighten the brake caliper bleed screw to 12 N.m (106 lb in).
2. Install the brake caliper bleed screw cap.
3. Lubricate the new piston seal and the brake caliper bore seal groove with brake fluid.
4. Install new the seal into the brake caliper bore seal groove.
5. Ensure that the seal is not twisted.
6. Lubricate the brake caliper bore and the piston with brake fluid.
7. Install the boot and the piston. Install the boot over the end of the piston so that the fold will face toward the brake caliper housing piston bore opening. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore. Push down the piston to the bottom of the brake caliper bore. Ensure that the boot properly seats into the piston groove and into the groove in the brake caliper bore. Repeat steps 5 and 6 for the remaining piston.
8. Install the brake caliper to the vehicle. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Disc Brake Hardware Replacement - Front

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
3. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
4. Remove the disc brake pads from the disc brake caliper mounting bracket.
5. Remove the disc brake pad retainers from the disc brake caliper mounting bracket.
6. Inspect the disc brake hardware. Refer to «Disc Brake Mounting and Hardware Inspection - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__disc-brake-mounting-and-hardware-inspection) .
7. Remove the caliper pin boots (4) from the disc brake caliper mounting bracket (3).

1. Lubricate the front brake caliper bushings, bolts and seals with high temperature silicone brake lubricant.
2. Install the caliper pin boots (4) to the disc brake caliper mounting bracket (3).
3. Install the disc brake pad retainers to the disc brake caliper mounting bracket.
4. Install the disc brake pads to the disc brake caliper mounting bracket.
5. Install the disc brake caliper to the caliper mounting bracket. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
6. With the engine OFF, gradually apply the brake pedal approximately 2/3 of its travel distance.
7. Slowly release the brake pedal.
8. Wait 15 seconds, then repeat steps 6-7 until a firm brake pedal is obtained. This will properly seat the brake caliper pistons and brake pads.

Disc Brake Hardware Replacement - Rear

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
3. Remove the brake caliper from the brake caliper mounting bracket and support the brake caliper with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake hose from the caliper. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
4. Remove the disc brake pads from the brake caliper mounting bracket.
5. Remove the disc brake pad retainers from the brake caliper mounting bracket.
6. Remove the caliper slide pins (5) from the brake caliper mounting bracket (3).
7. Remove the caliper slide pin boots (4) from the brake caliper mounting bracket.
8. Inspect the disc brake hardware. Refer to «Disc Brake Mounting and Hardware Inspection - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__disc-brake-mounting-and-hardware-inspection) .

1. Lubricate the brake caliper mounting bracket bushings and the caliper slide pins with high temperature silicone brake lubricant.
2. Install the caliper slide pin boots (4) to the disc brake caliper mounting bracket.
3. Install the caliper slide pins (5) to the brake caliper mounting bracket (3).
4. Install the disc brake pad retainers to the brake caliper mounting bracket.
5. Install the disc brake pads to the brake caliper mounting bracket.
6. Install the disc brake caliper to the brake caliper mounting bracket. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
7. With the engine OFF, gradually apply the brake pedal approximately 2/3 of it's travel distance.
8. Slowly release the brake pedal.
9. Wait 15 seconds, then repeat steps 7-8 until a firm brake pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
10. Lower the vehicle.

1. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Remove the brake pads.
3. Remove the anti-rattle clips from the brake caliper bracket.
4. Remove the brake caliper bracket mounting bolts (2).
5. Remove the brake caliper bracket (1).
6. Remove any contaminants or foreign material from the inside ends of the brake caliper bracket.
7. Clean the mounting surface and threads of the brake caliper bracket.

1. Install the brake caliper bracket (1).
2. Perform the following procedure before installing the brake caliper bracket mounting bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488).
3. Install the caliper bracket mounting bolts (2). Tighten: Tighten the brake caliper bracket to knuckle bolt to 175 N.m (121 lb ft) for the 15 Series. Tighten the brake caliper bracket to knuckle bolts to 300 N.m (221 lb ft) for 25/35 Series.
4. Install the anti-rattle clips to the brake caliper bracket.
5. Install the brake pads to the brake caliper bracket.
6. Slide the brake pads in until they contact the rotor.
7. Install the brake caliper. Refer to «Brake Caliper Replacement - Front»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
8. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
9. Lower the vehicle.
10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.
11. Slowly release the brake pedal.
12. Wait 15 seconds, then repeat steps 10-11 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.

Brake Caliper Bracket Replacement - Rear (35 Series)

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
3. Install a C-clamp over the body of the brake caliper, with the C-clamp ends against the rear of the caliper body and the outboard disc brake pad.
4. Slowly tighten the C-clamp until the pistons are pushed into the caliper bores enough to remove the caliper from the pads.
5. Remove the C-clamp from the caliper.
6. Loosen the rear brake caliper mounting bolts. Do not remove.
7. Remove the brake caliper bracket mounting bolts (2).
8. Remove the brake caliper bracket (1) and brake caliper as an assembly.
9. Remove the brake caliper mounting bolts from the brake caliper mounting bracket and support the brake caliper with heavy mechanic's wire or equivalent.
10. Remove the brake pads from the brake caliper mounting bracket.
11. Remove the anti-rattle clips from the brake caliper mounting bracket.

1. Install the anti-rattle clips to the brake caliper mounting bracket.
2. Install the brake pads to the brake caliper mounting bracket.
3. Install the brake caliper to the brake caliper mounting bracket.
4. Install the brake caliper mounting bolts to the brake caliper mounting bracket. Do not tighten.
5. Install the brake caliper and brake caliper mounting bracket (1) as an assembly.
6. Perform the following procedure before installing the brake caliper mounting bracket bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
7. Install the brake caliper mounting bracket bolts (2). Tighten: Tighten the brake caliper mounting bracket bolts to 300 N.m (221 lb ft).
8. Tighten the brake caliper mounting bolts (2). Tighten: Tighten the brake caliper mounting bolts to 108 N.m (80 lb ft).
9. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
10. Lower the vehicle.
11. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of it's travel distance.
12. Slowly release the brake pedal.
13. Wait 15 seconds, then repeat steps 11-12 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.

Brake Caliper Bracket Replacement - Rear (15/25 Series w/o NYS)

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
3. Remove the brake caliper from the brake caliper mounting bracket and support the brake caliper with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake hose from the brake caliper. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
4. Remove the brake pads from the brake caliper mounting bracket.
5. Remove the anti-rattle clips from the brake caliper bracket.
6. Remove the brake caliper bracket mounting bolts (2).
7. Remove the brake caliper bracket (1).
8. Remove any contaminants or foreign material from the inside ends of the brake caliper bracket.
9. Clean the mounting surface and threads of the brake caliper bracket.

1. Install the brake caliper bracket (1).
2. Perform the following procedure before installing the brake caliper bracket mounting bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
3. Install the caliper bracket mounting bolts (2). Tighten: For vehicles equipped with JH5 brake systems, tighten the caliper bracket mounting bolts to 200 N.m (148 lb ft). For vehicles equipped with JH6/JH7 brake systems, tighten the caliper bracket mounting bolts to 300 N.m (221 lb ft).
4. Install the anti-rattle clips to the brake caliper mounting bracket.
5. Install the brake pads to the brake caliper mounting bracket.
6. Slide the brake pads in until they contact the rotor.
7. Install the brake caliper. Refer to «Brake Caliper Replacement - Rear»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
8. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
9. Lower the vehicle.
10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of it's travel distance.
11. Slowly release the brake pedal.
12. Wait 15 seconds, then repeat steps 10-11 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.

Tools Required

1. J 41013 Rotor Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. J 42450-A Wheel Hub Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Scheme 18

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
3. Remove the front wheel hub extension, dual wheel vehicles only. Insert a drift or large screwdriver through the brake caliper into one of the brake rotor vanes in order to prevent the rotor from turning. Mark the relationship of the front wheel hub extension to the hub. Remove the front wheel hub extension bolts. Remove the front wheel hub extension from the vehicle. It may be necessary to tap around the perimeter of the hub extension with a rubber mallet to loosen it from the hub.
4. Mark the relationship of the rotor to the hub.
5. Install a C-clamp over the body of the brake caliper, with the C-clamp ends against the rear of the caliper body and the outboard disc brake pad.
6. Slowly tighten the C-clamp until the pistons are pushed into the caliper bores enough to remove the caliper from the pads.
7. Remove the C-clamp from the caliper.
8. Remove the brake caliper and brake caliper bracket as an assembly and support with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
9. Remove the rotor retaining push nuts from the wheel studs, if applicable.
10. It may be necessary to strike the end of the hub or the rotor with a deadblow hammer to separate the rotor from the hub.
11. Remove the rotor.
12. If the rotor is difficult to remove due to corrosion in the hub area use the following procedure to remove the rotor, 25 and 35 series only. Clean all the surface areas and the threaded holes of contamination. Generously apply penetrating oil or the equivalent to the hub/rotor area. Insert two M10 x 1.5 bolts or jack screws into the threaded holes of the rotor. Tighten both bolts evenly to force the rotor from the hub.

1. Use the J 42450-A to clean all rust and contaminants from the mating surface of the hub flange. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Use the J 41013 to clean all rust and contaminants from the inside diameter of the hat section of the brake rotor to prevent any foreign material from getting between the brake rotor and the hub flange. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. Inspect the mating surfaces of the hub/axle flange and the rotor to ensure that there are no foreign particles or debris remaining.
4. Align the rotor to its original position on the hub (if applicable) and install the rotor.
5. If the brake rotor was removed and installed as part of a brake system repair, measure the assembled lateral runout (LRO) of the brake rotor to ensure optimum performance of the disc brakes. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
6. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Correction»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
7. Install the caliper and caliper bracket assembly.
8. Perform the following procedure before installing the brake caliper bracket mounting bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
9. Install the caliper bracket mounting bolts. Tighten: Tighten the brake caliper bracket mounting bolts to 175 N.m (121 lb ft) (15 Series). Tighten the brake caliper bracket mounting bolts to 300 N.m (221 lb ft) (25 and 35 Series).
10. Install the front wheel hub extension (dual wheel vehicles only). Insert a drift or large screwdriver through the brake caliper into one of the brake rotor vanes in order to prevent the rotor from turning. Align and install the front wheel hub extension to the original position on the hub. IMPORTANT: Follow the same tightening sequence for the front wheel hub extension that is used on an eight lug wheel. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels. Install the front wheel hub extension nuts. Tighten: Tighten the front wheel hub extension nuts to 130 N.m (96 lb ft).
11. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
12. Lower the vehicle.
13. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.
14. Slowly release the brake pedal.
15. Wait 15 seconds, then repeat steps 13-14 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
16. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.

Brake Rotor Replacement - Rear (W/Dual Wheels)

1. Release the park brake.
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
4. Remove the hub and rotor assembly. Refer to «Rear Axle Hub, Bearing, Cup, and/or Seal Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle__rear-axle-hub-bearing-cup-andor) in Rear Drive Axle.
5. Mark the relationship of the hub to the rotor.
6. Place the hub and rotor assembly on a hydraulic press.
7. Press the wheel studs out of the hub and rotor assembly.

Scheme 19

1. Align the hub and the rotor (if applicable).
2. Install each of the new wheel studs into the hub and rotor assembly by performing the following steps: Install the stud. Install 4 washers to the stud. Install a lug nut to the stud with the flat side of the nut towards the washers. Tighten the lug nut to draw the stud into the hub and rotor assembly. Inspect the hub and rotor assembly to ensure that the hub is tight against the rotor and the stud is seated completely. Remove the lug nut and the washers.
3. Install the hub and rotor assembly to the vehicle. Refer to «Rear Axle Hub, Bearing, Cup, and/or Seal Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle__rear-axle-hub-bearing-cup-andor) in Rear Drive Axle.
4. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
5. Lower the vehicle.
6. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of it's travel distance.
7. Slowly release the brake pedal.
8. Wait 15 seconds, then repeat steps 6-7 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
9. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.

Brake Rotor Replacement - Rear (Except Dual Wheels)

Tools Required

1. J 2619-01 Slide Hammer With Adapter. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. J 41013 Rotor Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. J 42450-A Wheel Hub Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
4. J-46277 Rotor Removal Tool. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Scheme 20

1. Release the park brake.
2. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
4. Mark the relationship of the rotor to the hub.
5. Install a C-clamp over the body of the brake caliper, with the C-clamp ends against the rear of the caliper body and the outboard disc brake pad.
6. Slowly tighten the C-clamp until the pistons are pushed into the caliper bores enough to remove the caliper from the pads.
7. Remove the C-clamp from the caliper.
8. Remove the brake caliper bracket mounting bolts.
9. Remove the brake caliper and brake caliper bracket as an assembly and support with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
10. Remove the rotor retaining push nuts from the wheel studs, if applicable.
11. It may be necessary to strike the end of the hub or the rotor with a deadblow hammer to separate the rotor from the hub.
12. Remove the brake rotor. Do not force the rotor off. If the rotor is difficult to remove, ease it off by gently rotating it as you pull outward.
13. If the brake rotor cannot be removed perform the following: Assemble J-46277 to J 2619-01 . See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Insert J-46277 between the rotor friction surfaces in the vent section of the rotor. DO NOT place the J-46277 on the rotor friction surface. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Using J-46277 and J 2619-01 remove the rotor from the hub assembly. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Inspect the park brake components for the following conditions: Bent or broken hold down spring Broken, cracked or worn brake shoe lining Bent or damaged brake shoe Worn, bent or damaged backing plate If any of these conditions are found replace the affected parts.

1. Use the J 42450-A to clean all rust and contaminants from the mating surface of the hub flange. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Use the J 41013 to clean all rust and contaminants from the inside diameter of the hat section of the brake rotor to prevent any foreign material from getting between the brake rotor and the hub flange. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. Inspect the mating surfaces of the hub/axle flange and the rotor to ensure that there are no foreign particles or debris remaining.
4. Align the rotor to its original position on the hub, if applicable, and install the rotor.
5. If the brake rotor was removed and installed as part of a brake system repair, measure the assembled lateral runout (LRO) of the brake rotor to ensure optimum performance of the disc brakes. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
6. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Correction»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
7. Install the rotor by slowly turning the rotor while pushing the rotor towards the axle.
8. Install the caliper and the bracket as an assembly to the vehicle.
9. Perform the following procedure before installing the caliper bracket mounting bolts. Remove all traces of the original adhesive patch. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
10. Install the caliper bracket mounting bolts. Tighten: For vehicles with JH5, tighten the brake caliper bracket mounting bolts to 200 N.m (148 lb ft). For vehicles with JH6/JH7, tighten the brake caliper bracket mounting bolts to 300 N.m (221 lb ft).
11. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
12. Lower the vehicle.
13. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of it's travel distance.
14. Slowly release the brake pedal.
15. Wait 15 seconds, then repeat steps 13-14 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
16. Fill the master cylinder reservoir to the proper level with clean brake fluid. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) in Hydraulic Brakes.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
3. Remove the hub and bearing assembly (5). Refer to «Wheel Hub, Bearing, and Seal Replacement (RWD)»(/chevrolet/chevy-express-g3500/1996-2012/remont/suspension-front/#front-suspension-system) or «Wheel Hub, Bearing, and Seal Replacement (4WD)»(/chevrolet/chevy-express-g3500/1996-2012/remont/suspension-front/#front-suspension-system) in Front Suspension.
4. Remove the splash shield (6), for 15 series.
5. Remove the splash shield, for 25/35 series.

1. Install the splash shield (6), for 15 series.
2. Install the splash shield, for 25/35 series.
3. Install the hub and bearing assembly (5). Refer to «Wheel Hub, Bearing, and Seal Replacement (RWD)»(/chevrolet/chevy-express-g3500/1996-2012/remont/suspension-front/#front-suspension-system) or «Wheel Hub, Bearing, and Seal Replacement (4WD)»(/chevrolet/chevy-express-g3500/1996-2012/remont/suspension-front/#front-suspension-system) in Front Suspension.
4. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
5. Remove the safety stands.
6. Lower the vehicle.

Disc Brake Backing Plate Replacement - Rear

Scheme 21

1. Disable the park brake cable automatic adjuster. Refer to «Disabling the Park Brake Cable Automatic Adjuster»(/chevrolet/chevy-express-g3500/1996-2012/remont/parking-brake-system/#parking-brake-system__disabling-the-park-brake-cable-automatic) in Park Brake.
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/chevy-express-g3500/1996-2012/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
4. Perform the following procedure to remove the cable (2) from the backing plate (4): Compress the spring (3) by pushing towards the lever (1). Depress the locking tabs. Pull the cable housing out of the backing plate (4). Remove the cable (2) through the slot in the backing plate.
5. Remove the park brake cable (2) from the lever (1).
6. For the 15 and 25 series, perform the following steps: Remove the rotor. Refer to «Brake Rotor Replacement - Rear (W/Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-wdual) or «Brake Rotor Replacement - Rear (Except Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-except) . Remove the axle shaft. Refer to «Rear Axle Shaft Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle) in Rear Drive Axle.
7. For the 35 series with single rear wheels, perform the following steps: Remove the rotor. Refer to «Brake Rotor Replacement - Rear (W/Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-wdual) or «Brake Rotor Replacement - Rear (Except Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-except) . Remove the hub assembly. Refer to «Rear Axle Hub, Bearing, Cup, and/or Seal Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle__rear-axle-hub-bearing-cup-andor) in Rear Drive Axle.
8. For the 35 series with dual rear wheels, remove the hub and rotor assembly. Refer to «Rear Axle Hub, Bearing, Cup, and/or Seal Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle__rear-axle-hub-bearing-cup-andor) in Rear Drive Axle.
9. Remove the park brake shoe. Refer to «Park Brake Shoe Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/parking-brake-system/#parking-brake-system) .
10. Remove the backing plate nuts.
11. Remove the backing plate from the axle housing flange.

1. Install the backing plate to the axle housing flange.
2. Install the backing plate nuts. Tighten: Without dual rear wheels - Tighten the backing plate bolts to 135 N.m (100 lb ft). With dual rear wheels - Tighten the backing plate bolts to 160 N.m (118 lb ft) plus 30 degrees.
3. Install the park brake shoe. Refer to «Park Brake Shoe Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/parking-brake-system/#parking-brake-system) .
4. For the 15 and 25 series, perform the following steps: Install the axle shaft. Refer to «Rear Axle Shaft Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle) in Rear Drive Axle. Install the rotor. Refer to «Brake Rotor Replacement - Rear (W/Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-wdual) or «Brake Rotor Replacement - Rear (Except Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-except) .
5. For the 35 series with single rear wheels, perform the following steps: Install the hub assembly. Refer to «Rear Axle Hub, Bearing, Cup, and/or Seal Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle__rear-axle-hub-bearing-cup-andor) in Rear Drive Axle. Install the rotor. Refer to «Brake Rotor Replacement - Rear (W/Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-wdual) or «Brake Rotor Replacement - Rear (Except Dual Wheels)»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-replacement-rear-except) .
6. For the 35 series with dual rear wheels, install the hub and rotor assembly. Refer to «Rear Axle Hub, Bearing, Cup, and/or Seal Replacement»(/chevrolet/chevy-express-g3500/1996-2012/remont/differentials-drive-axles/#rear-drive-axle__rear-axle-hub-bearing-cup-andor) in Rear Drive Axle.
7. Adjust the park brake shoe. Refer to «Park Brake Adjustment»(/chevrolet/chevy-express-g3500/1996-2012/remont/parking-brake-system/#parking-brake-system__park-brake-adjustment) .
8. Install the park brake cable (2) to the lever (1).
9. Perform the following procedure to install the cable (2) to the backing plate (4): Compress the spring (3) by pushing towards the lever (1). Route the cable (2) through the slot in the backing plate. Push the cable housing into the backing plate (4) until the locking tabs snap into place.
10. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
11. Remove the safety stands.
12. Lower vehicle.
13. Enable the park brake cable automatic adjuster. Refer to «Enabling the Park Brake Cable Automatic Adjuster»(/chevrolet/chevy-express-g3500/1996-2012/remont/parking-brake-system/#parking-brake-system__enabling-the-park-brake-cable-automatic) in Park Brake.

Brake Rotor Assembled Lateral Runout (LRO) Correction

Review the following acceptable methods for bringing the brake rotor assembled LRO to within specifications. Determine which method to use for the specific vehicle being repaired.

1. «Brake Rotor Assembled Lateral Runout (LRO) Correction - Indexing»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) The indexing method of correcting assembled LRO is most effective when the LRO specification is only exceeded by a relatively small amount: 0.025-0.127 mm (0.001-0.005 in). Indexing is used to achieve the best possible match of high spots to low spots between related components.
2. «Brake Rotor Assembled Lateral Runout (LRO) Correction - On-Vehicle Lathe»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) The on-vehicle brake lathe method is used to bring the LRO to within specifications through compensating for LRO while refinishing the brake rotor.

If the assembled LRO cannot be corrected using these methods, then other components must be suspected as causing and/or contributing to the LRO concern.

Brake Rotor Assembled Lateral Runout (LRO) Correction - Indexing

Tools Required

1. J 39544-KIT Torque-Limiting Socket Set, or equivalent. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. J 45101-100 Conical Brake Rotor Washers. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

1. Remove the J 45101-100 and the lug nuts that were installed during the assembled LRO measurement procedure. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Inspect the mating surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles or debris remaining.
3. Index the brake rotor in a different orientation to the hub/axle flange.
4. Hold the rotor firmly in place against the hub/axle flange and install one of the J 45101-100 (1) and one lug nut (2) onto the upper-most wheel stud. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
5. Continue to hold the rotor secure and tighten the lug nut firmly by hand.
6. Install the remaining J 45101-100 and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
7. Using the J 39544-KIT , or equivalent, tighten the lug nuts in a star-pattern to specification, in order to properly secure the rotor. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) . Refer to «Tire and Wheel Removal and Installation»(/chevrolet/chevy-express-g3500/1996-2012/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) in Tires and Wheels.
8. Measure the assembled LRO of the brake rotor. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
9. Compare the amount of change between this measurement and the original measurement.
10. If this measurement is within specifications, proceed to step 14.
11. If this measurement still exceeds specifications, repeat steps 1-9 until the best assembled LRO measurement is obtained.
12. Matchmark the final location of the rotor to the wheel studs if the orientation is different than it was originally.
13. If the brake rotor assembled LRO measurement still exceeds the maximum allowable specification, refer to «Brake Rotor Assembled Lateral Runout (LRO) Correction»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
14. If the brake rotor assembled LRO is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the J 45101-100 and the lug nuts. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Brake Rotor Assembled Lateral Runout (LRO) Correction - On-Vehicle Lathe

Tools Required: J 45101-100 Conical Brake Rotor Washers. See Special Tools and Equipment .

1. Ensure that the caliper and caliper bracket that are already being supported, are clear from contacting any rotating components, such as the brake rotor.
2. Remove the J 45101-100 and the lug nuts that were installed during the assembled LRO measurement procedure and/or the indexing correction procedure. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. Inspect the mounting surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles or debris remaining.
4. Set up the lathe, following the manufacturer's instructions.
5. Refinish the brake rotor, following the brake lathe manufacturer's instructions.
6. After each successive cut, inspect the brake rotor thickness. Refer to «Brake Rotor Thickness Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-thickness-measurement) .
7. If at any time the brake rotor exceeds the minimum allowable thickness after refinish specification, the brake rotor must be replaced. After replacing the rotor, proceed to step 10.
8. After refinishing the brake rotor, use the following procedure in order to obtain the desired non-directional finish: Follow the brake lathe manufacturer's recommended speed setting for applying a non-directional finish Using moderate pressure, apply the non-directional finish: If the lathe is equipped with a non-directional finishing tool, apply the finish with 120 grit aluminum oxide sandpaper If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding block and 150 grit aluminum oxide sandpaper After applying a non-directional finish, clean each friction surface of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner
9. Remove the lathe from the vehicle.
10. Measure the assembled LRO of the brake rotor. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
11. If the brake rotor assembled LRO measurement still exceeds the maximum allowable specification, refer to «Brake Rotor Assembled Lateral Runout (LRO) Correction»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
12. If the brake rotor assembled LRO is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the J 45101-100 and the lug nuts. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

Brake Rotor Refinishing

Tools Required

1. J 41013 Rotor Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. J 42450-A Wheel Hub Resurfacing Kit. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .

1. Using the J 42450-A , thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
2. Using the J 41013 , thoroughly clean any rust or corrosion from the mating surface and mounting surface of the brake rotor. See «Special Tools and Equipment»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system) .
3. Inspect the mating surfaces of the hub/axle flange and the rotor to ensure that there are no foreign particles or debris remaining.
4. Mount the brake rotor to the brake lathe according to the lathe manufacturer's instructions, ensuring that all mounting attachments and adapters are clean and free of debris.
5. Ensure that any vibration dampening attachments are securely in place.
6. With the brake lathe running, slowly bring in the cutting tools until they just contact the brake rotor friction surfaces.
7. Observe the witness mark on the brake rotor. If the witness mark extends approximately three-quarters or more of the way around the brake rotor friction surface on each side, the brake rotor is properly mounted to the lathe.
8. If the witness mark does not extend three-quarters or more of the way around the brake rotor, re-mount the rotor to the lathe.
9. Following the brake lathe manufacturer's instructions, refinish the brake rotor.
10. After each successive cut, inspect the brake rotor thickness. Refer to «Brake Rotor Thickness Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-thickness-measurement) .
11. If at any time the brake rotor exceeds the minimum allowable thickness after refinish specification, the brake rotor must be replaced.
12. After refinishing the brake rotor, use the following procedure in order to obtain the desired non-directional finish: Follow the brake lathe manufacturer's recommended speed setting for applying a non-directional finish Using moderate pressure, apply the non-directional finish: If the lathe is equipped with a non-directional finishing tool, apply the finish with 120 grit aluminum oxide sandpaper If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding block and 150 grit aluminum oxide sandpaper After applying a non-directional finish, clean each friction surface of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner
13. Remove the brake rotor from the brake lathe.
14. Measure the assembled lateral runout (LRO) of the brake rotor to ensure optimum performance of the disc brakes. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Measurement»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .
15. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to «Brake Rotor Assembled Lateral Runout (LRO) Correction»(/chevrolet/chevy-express-g3500/1996-2012/remont/mechanical-hydraulic/#disc-brake-system__brake-rotor-assembled-lateral-runout-lro) .

System Component Description

The disc brake system consists of the following components

System Operation

Mechanical output force is applied from the hydraulic brake caliper pistons to the inner brake pads. As the pistons press the inner brake pads outward, the caliper housings draw the outer brake pads inward. This allows the output force to be equally distributed. The brake pads apply the output force to the friction surfaces on both sides of the brake rotors, which slows the rotation of the tire and wheel assemblies. The correct function of both the brake pad and brake caliper hardware is essential for even distribution of braking force.

Special Tools

Special Tools Illustration Tool Number/Description J 2619-01 Slide Hammer w/Adapter J 8001 Dial Indicator Set J 39544-KIT Torque-Limiting Socket Set J 41013 Rotor Resurfacing Kit J 42450-A Wheel Hub Resurfacing Kit J 45101 Hub and Wheel Runout Gage J 45101-100 Conical Brake Rotor Washers J 45515 Brake Caliper Piston Boot Seal Installer J 46277 Rotor Removal Tool

Scheme 22

Scheme 23

Scheme 24

Scheme 25

Scheme 26

Scheme 27

Scheme 28

Scheme 29

See also:
• Diagnostic Starting Point - Hydraulic Brakes
• Brake Dust Caution
• Tire and Wheel Removal and Installation
• Brake Fluid Irritant Caution
• Lifting and Jacking the Vehicle
• Master Cylinder Reservoir Filling
• Brake Fluid Effects on Paint and Electrical Components Notice
• Fastener Notice
• Hydraulic Brake System Bleeding (Manual)
• Rear Axle Hub, Bearing, Cup, and/or Seal Replacement
• Wheel Hub, Bearing, and Seal Replacement (RWD)
• Disabling the Park Brake Cable Automatic Adjuster
• Rear Axle Shaft Replacement
• Park Brake Shoe Replacement
• Park Brake Adjustment
• Enabling the Park Brake Cable Automatic Adjuster
• Brake Pads Replacement - Front
• Brake Rotor Thickness Variation Measurement
• Brake Rotor Replacement - Rear (W/Dual Wheels)
• Brake Rotor Replacement - Rear (Except Dual Wheels)
• Brake Rotor Refinishing
• Brake Rotor Assembled Lateral Runout (LRO) Correction
• Burnishing Pads and Rotors
• Disc Brake Mounting and Hardware Inspection - Front
• Brake Rotor Thickness Measurement