Trim Height Specifications
| Model | Option | Service Allowed | Service Preferred | Cross Z Trim Height, L-R | Cross D Trim Height, L-R |
|---|---|---|---|---|---|
| Z Trim Height: All G1500/2500/3500 specs are ±14 mm and H1500 specs are ±6 mm. | |||||
| G1500/G2500 W/7300 GVW | All | 84-112 mm (3.3-4.4 in) | 98 mm (3.8 in) | 0 ± 12 mm (0.47 in) | 0 ± 12 mm (0.47 in) |
| G2500 W/8600 GVWG3500 Including 14,200 GVW | All | 94-122 mm (3.7-4.8 in) | 108 mm (4.3 in) | 0 ± 12 mm (0.47 in) | 0 ± 12 mm (0.47 in) |
| H1500 | YF7 | 116-128 mm (4.6-5.0 in) | 122 mm (4.8 in) | 0 ± 12 mm (0.47 in) | 0 ± 12 mm (0.47 in) |
| H1500 | W/o YF7 | 106-118 mm (4.2-4.6 in) | 112 mm (4.4 in) | 0 ± 12 mm (0.47 in) | 0 ± 12 mm (0.47 in) |
Trim Height Specifications
Symptoms - Suspension General Diagnosis
| IMPORTANT | The following steps must be completed before using the symptom tables. |
- Determine whether the vehicle is equipped with an electrically assisted or active suspension system. Perform electrical diagnosis prior to beginning mechanical diagnosis. Refer to «Diagnostic Starting Point - Vehicle»(/chevrolet/express-g2500/2013-2013/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-starting-point-vehicle) .
- Review the system description and operation in order to familiarize yourself with the system functions. Refer to the appropriate description and operation: «General Description (Coil Spring)»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#front-suspension-system__general-description-coil-spring) , «General Description (Torsion Bar)»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#front-suspension-system__general-description-torsion-bar) for the front suspension «General Description»(/chevrolet/express-g2500/2013-2013/remont/suspension-rear/#rear-suspension-system__general-description) for the rear suspension «General Description»(/chevrolet/express-g2500/2013-2013/remont/wheel-tire-system/#tires-and-wheels__general-description) for the tires and wheels
Visual/Physical Inspection
- Inspect for aftermarket devices which could affect the operation of any of the suspension subsystems.
- Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
- Inspect for proper tire size and inflation pressure. Refer to «Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label»(/chevrolet/express-g2500/2013-2013/remont/hoistjack/#general-information) .
Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom
- «Ride Diagnosis»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__ride-diagnosis)
- «Vehicle Leads/Pulls»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__vehicle-leadspulls)
- «Body Leans or Sways in Corners»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__body-leans-or-sways-in-corners)
- «Suspension Bottoms»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__suspension-bottoms)
- «Memory Steer»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__memory-steer)
- «Noise Diagnosis - Front Suspension»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__noise-diagnosis-front-suspension)
- «Noise Diagnosis - Rear Suspension»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__noise-diagnosis-rear-suspension)
- «Suspension Strut and Shock Absorber Testing - On Vehicle»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__suspension-strut-and-shock-absorber-testing)
- «Wheel Bearings Diagnosis»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__wheel-bearings-diagnosis)
- «Radial Tire Lead/Pull Correction»(/chevrolet/express-g2500/2013-2013/remont/wheel-tire-system/#tires-and-wheels__radial-tire-leadpull-correction)
Ride Diagnosis
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | IMPORTANT: Verify the vehicle suspension package RPO. Verify that the ride is too soft or too hard.Does the vehicle ride normally? | System OK | Go to Step 3 |
| 3 | Check the tire inflation and adjust to specifications. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label . Did you adjust the tire pressure? | Go to Step 6 | Go to Step 4 |
| 4 | Inspect the vehicle trim height. Refer to Trim Height Inspection . Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 5 | Inspect the following suspension components for wear or damage: Shock Absorbers-Refer to Suspension Strut and Shock Absorber Testing - On Vehicle . Springs Did you find and correct the condition? | Go to Step 6 | |
| 6 | Drive the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Verify the vehicle suspension package RPO. |
Ride Diagnosis
Vehicle Leads/Pulls
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: At a constant highway speed on a typical straight road, lead/pull is the amount of effort required at the steering wheel to maintain the vehicle's straight path. | |||
| 1 | Did you review the General Description and perform the visual/physical inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Road test the vehicle in order to verify the complaint. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | Inspect the tire/wheel assemblies for the following conditions: Correct tire pressure-Refer to the tire placard. Correct tire size-Refer to the tire placard. Abnormal tire wear or damage Did you find and correct the condition? | Go to Step 9 | Go to Step 4 |
| 4 | Perform the Radial Tire Lead/Pull Correction . Did you find and correct the condition? | Go to Step 9 | Go to Step 5 |
| 5 | Inspect and correct/adjust the suspension and steering systems for the following conditions: Vehicle trim height-Refer to Trim Height Specifications . Excessively worn, loose, or damaged components Did you find and correct the condition? | Go to Step 9 | Go to Step 6 |
| 6 | Inspect the brake system for brake drag. With the vehicle suspended on a hoist, brake drag can be identified by rotating each wheel several times and observing whether more force is need to rotate the left wheel or the right wheel. Refer to Brake Rotor Thickness Variation Measurement . Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
| 7 | Inspect the wheel alignment and adjust as necessary. Refer to Wheel Alignment Measurement . Did you correct the condition? | Go to Step 9 | Go to Step 8 |
| 8 | Inspect the steering gear for unequal effort. The vehicle must be suspended on a hoist, the engine running, and the transmission in PARK or NEUTRAL. Grasp the tire assembly and manually simulate a turn from the left of center and the right of center observing whether more force is needed to turn to the left or to the right. If this condition exists replace the steering gear. Did you correct the condition? | System OK | Go to Step 3 |
| 9 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Vehicle Leads/Pulls
Body Leans or Sways in Corners
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify the vehicle leans or sways in corners. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | Inspect the following components for wear or damage: Rear Coil Springs Front Coil Springs Are the components worn or damaged? | Go to Step 5 | Go to Step 4 |
| 4 | Inspect the stabilizer shaft link for wear or damage. Repair as necessary. Did you find and correct the condition? | Go to Step 6 | Go to Step 2 |
| 5 | Replace the springs as necessary. Did you complete the repair? | Go to Step 6 | |
| 6 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Body Leans or Sways in Corners
Suspension Bottoms
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: A loud bang or thump that can usually be felt and/or heard when the vehicle is driven over bumps. This condition is commonly noticed when the vehicle trim height is too low. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that the suspension bottoms. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | Inspect for vehicle overloading and correct the overloading condition as necessary. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label for specifications. Did you find and correct the condition? | Go to Step 6 | Go to Step 4 |
| 4 | Inspect the following components: Inspect the shock absorbers. Refer to Suspension Strut and Shock Absorber Testing - On Vehicle . Inspect for damaged coil springs, torsion bar or leaf springs and replace as necessary. Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 5 | Inspect the vehicle trim height. Refer to Trim Height Inspection . Did you complete the trim height inspection procedure? | Go to Step 6 | |
| 6 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Suspension Bottoms
Memory Steer
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: The steering wheel does not return to center after completing a turn. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that memory steer is present. Does the system operate normally? | System OK | Go to Step 3 |
| 3 | Check the tire inflation and adjust to specifications. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label . Did you adjust the tire pressure? | Go to Step 14 | Go to Step 4 |
| 4 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Lubricate the tie rod ends and the ball joints if applicable. Inspect the suspension system for worn or damaged components. Repair as necessary. Did you find and correct the condition? | Go to Step 14 | Go to Step 5 |
| 5 | Rotate the steering wheel ONE revolution in both directions. Rotate the steering wheel back to the original position. Was the steering wheel abnormally difficult to rotate in either direction? | Go to Step 6 | Go to Step 7 |
| 6 | Remove the steering column pinch bolt in order to disengage the steering column from the intermediate shaft. IMPORTANT: Do NOT rotate the steering wheel more than one complete revolution. Note the position of the steering wheel and rotate the steering wheel ONE revolution in both directions. Rotate the steering wheel back to the original position. Was the steering wheel abnormally difficult to rotate in either direction? | Go to Step 13 | Go to Step 7 |
| 7 | Remove the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation (6-Lug Wheel) , Tire and Wheel Removal and Installation (8-Lug Wheel) . Disconnect both of the outer tie rod ends from the steering knuckles. Refer to Steering Linkage Outer Tie Rod Replacement , or Steering Linkage Outer Tie Rod Replacement . Use your hands in order to move the tie rod ends. Are either of the tie rod ends abnormally difficult to move? | Go to Step 10 | Go to Step 8 |
| 8 | Inspect for binding ball joints. Use your hands to push and pull the steering knuckle inboard and outboard. Are either of the steering knuckles abnormally difficult to move? | Go to Step 11 | Go to Step 9 |
| 9 | Inspect the wheel alignment and adjust as necessary. Refer to Wheel Alignment Measurement . Did you complete the wheel alignment? | Go to Step 14 | |
| 10 | Replace the outer tie rod end. Refer to Steering Linkage Outer Tie Rod Replacement . Did you complete the repair? | Go to Step 14 | |
| 11 | Replace the lower ball joint. Refer to Lower Control Arm Ball Joint Replacement (3500) , Lower Control Arm Ball Joint Replacement (1500, 2500) . Did you complete the repair? | Go to Step 14 | |
| 12 | Replace the steering gear. Refer to Steering Gear Replacement (Rack and Pinion) , Steering Gear Replacement (Recirculating Ball) . Did you complete the repair? | Go to Step 14 | |
| 13 | Repair the steering column as necessary. Refer to Steering Column Replacement . Did you complete the repair? | Go to Step 14 | |
| 14 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Do NOT rotate the steering wheel more than one complete revolution. |
Memory Steer
Noise Diagnosis - Front Suspension
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Any noise emitted from the front of the vehicle that is induced by VEHICLE SPEED or DRIVING TERRAIN as related to the front suspension. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Attempt to duplicate the condition. Road test the vehicle. Did you duplicate the condition? | Go to Step 3 | System OK |
| 3 | Is the noise reactive to vehicle load or speed? | Go to Step 4 | Go to Step 7 |
| 4 | Inspect the tires for the following condition: Proper tire Inflation and adjust as necessary-Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label . Unusual tire wear-Refer to Vibration Analysis - Tire and Wheel . Inspect the wheel nuts for looseness and tighten as necessary. Refer to Fastener Tightening Specifications . Did you find and correct the condition? | Go to Step 14 | Go to Step 5 |
| 5 | Inspect the front wheel bearings. Refer to Wheel Bearings Diagnosis . Did you find and correct the condition? | Go to Step 14 | Go to Step 6 |
| 6 | If applicable inspect for front axle or transaxle noises. Refer to Symptoms - Front Drive Axle , or Symptoms - Automatic Transmission for the 4L60-E/4L65-E Transmission. Did you find and correct the condition? | Go to Step 14 | Go to Step 7 |
| 7 | Bounce the front of the vehicle in order to duplicate the noise. Did you duplicate the noise? | Go to Step 8 | Go to Step 9 |
| 8 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Inspect the front suspension components for looseness. Refer to Fastener Tightening Specifications . Inspect the front suspension components for damage and repair as necessary. Did you find and correct the condition? | Go to Step 14 | Go to Step 9 |
| 9 | Install the J 39570 chassis ear or equivalent. Bounce the front of the vehicle, using the J 39570 chassis ear or equivalent in order to locate the source of the noise. If necessary road test the vehicle. Repair or replace any damaged components as necessary. Did you find and correct the condition? | Go to Step 14 | Go to Step 10 |
| 10 | Inspect the ball joints and steering components for the following conditions: Lack of lubrication where applicable Looseness in the ball joints-Refer to Symptoms - Suspension General Diagnosis . Looseness in the steering linkage-Refer to Steering Linkage Inspection . Looseness in the tie rods-Refer to Steering Linkage Outer Tie Rod Replacement , or Steering Linkage Outer Tie Rod Replacement . Did you find and correct the condition? | Go to Step 14 | Go to Step 11 |
| 11 | Inspect for damaged shock absorbers. Refer to Suspension Strut and Shock Absorber Testing - On Vehicle . Did you find and correct the condition? | Go to Step 14 | Go to Step 12 |
| 12 | Inspect the front stabilizer shaft and stabilizer shaft links for damage and repair as necessary. Refer to Stabilizer Shaft Replacement , or Stabilizer Shaft Link Replacement . Did you find and correct the condition? | Go to Step 14 | Go to Step 13 |
| 13 | Inspect for control arm damage and repair as necessary. Refer to Lower Control Arm Replacement (4 Wheel Drive) , Lower Control Arm Replacement (RWD) , and Upper Control Arm Replacement . Did you find and correct the condition? | Go to Step 14 | |
| 14 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Noise Diagnosis - Front Suspension
Noise Diagnosis - Rear Suspension
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Any noise emitted from the rear of the vehicle that is induced by VEHICLE SPEED or DRIVING TERRAIN as related to the rear suspension. | |||
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Attempt to duplicate the condition. Road test the vehicle. Did you duplicate the condition? | Go to Step 3 | System OK |
| 3 | Is the noise reactive to vehicle load or speed? | Go to Step 4 | Go to Step 6 |
| 4 | Perform the following inspections: Inspect and adjust the tire Inflation. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label . Inspect for unusual tire wear. Refer to Vibration Analysis - Tire and Wheel . Inspect the wheel nuts for looseness. Refer to Fastener Tightening Specifications . Did you find and correct the condition? | Go to Step 10 | Go to Step 5 |
| 5 | Inspect the rear axle for rear axle noises. Refer to Symptoms - Rear Drive Axle . Did you find and correct the condition? | Go to Step 10 | Go to Step 6 |
| 6 | Bounce the rear of the vehicle in order to duplicate the noise. Did you duplicate the noise? | Go to Step 7 | Go to Step 9 |
| 7 | Raise the vehicle. Refer to Lifting and Jacking the Vehicle . Inspect the rear suspension components for looseness and tighten as necessary. Refer to Fastener Tightening Specifications . Inspect the rear suspension components for damage and repair as necessary. Did you find and correct the condition? | Go to Step 10 | Go to Step 8 |
| 8 | Inspect the rear shock absorber. Refer to Suspension Strut and Shock Absorber Testing - On Vehicle . Did you complete the inspection? | Go to Step 10 | Go to Step 9 |
| 9 | Install the J 39570 chassis ear or equivalent. Bounce the rear of the vehicle, using the J 39570 chassis ear or equivalent, in order to locate the source of the noise. If necessary road test the vehicle. Repair or replace any defective component as necessary. Did you find and correct the condition? | Go to Step 10 | System OK |
| 10 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
Noise Diagnosis - Rear Suspension
Lower Control Arm Ball Joint Inspection
Special Tools
J 8001 Dial Indicator
For equivalent regional tools, refer to Special Tools .
- Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/express-g2500/2013-2013/remont/hoistjack/#general-information) .
- Clean and inspect the ball joint seal for cuts or tears. If the ball joint seal is damaged, replace the ball joint or the lower control arm as applicable for this vehicle.
- Support the lower control arm with a floor stand as far outboard as possible and raise the suspension until the lower control arm moves 25 mm (1 in).
- Install the J 8001 dial indicator , or suitable dial indicator, to measure the vertical lash in the ball joint.
- Lift the knuckle towards the lower control arm and record the dial indicator measurement.
- If the dial indicator reading is more than 0.50 mm (0.020 in), replace the ball joint or the lower control arm as applicable for this vehicle.
Upper Control Arm Ball Joint Inspection
Special Tools
J 8001 Dial Indicator Set
For equivalent regional tools, refer to Special Tools .
- Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/express-g2500/2013-2013/remont/hoistjack/#general-information) .
- Clean and inspect the ball joint seal for cuts or tears. If the ball joint seal is damaged, replace the ball joint or upper control arm as applicable for this vehicle.
- Support the lower control arm with a floor stand as far outboard as possible and raise the suspension until the lower control arm moves 25 mm (1 in).
- Install the J 8001 dial indicator , or suitable dial indicator, to measure the vertical lash in the ball joint.
- Apply downward force to the upper control arm and zero the indicator.
- Apply upward force to the upper control arm and check the dial indicator. Record the measurement
- If the dial indicator reading is more than 0.50 mm (0.020 in), replace the ball joint or the upper control arm as applicable for this vehicle.
Suspension Strut and Shock Absorber Testing - On Vehicle
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis |
| 2 | Verify that the customer's concern is present. Does the vehicle operate normally? | System OK | Go to Step 3 |
| 3 | IMPORTANT: A light film of oil on the top portion of the shock reservoir is normal. Inspect each strut or shock absorber for external fluid leakage.Is a strut or shock absorber leaking? | Go to Step 5 | Go to Step 4 |
| 4 | Use your hands in order to lift up and push down each corner of the vehicle 3 times. Remove your hands from the vehicle. Locate a shock or strut that exceeds 2 cycles. Did you locate a shock or strut that exceeds 2 cycles? | Go to Step 5 | Go to Step 6 |
| 5 | IMPORTANT: Inspect the vehicle trim height in order to correct any possible causes of shock/strut failures. Refer to Trim Height Inspection . Replace the strut or shock absorber. Refer to Shock Absorber Replacement (RWD) , Shock Absorber Replacement (4WD) , for the front suspension or Shock Absorber Replacement for the rear suspension.Did you complete the repair? | Go to Step 6 | |
| 6 | Operate the vehicle in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| A light film of oil on the top portion of the shock reservoir is normal. |
| IMPORTANT |
|---|
| Inspect the vehicle trim height in order to correct any possible causes of shock/strut failures. Refer to Trim Height Inspection . |
Suspension Strut and Shock Absorber Testing - On Vehicle
Wheel Bearings Diagnosis
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| 1 | Did you review the General Description and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Suspension General Diagnosis | |
| 2 | Road test the vehicle in order to verify the customer complaint. Does the vehicle operate normally? | System OK | Go to Step 3 | |
| 3 | Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Inspect for tire or wheel damage. Refer to Tire and Wheel Assembly Runout Measurement - On-Vehicle . Did you find and correct the condition? | Go to Step 7 | Go to Step 4 | |
| 4 | Install the J 39570 chassis ear . Road test the vehicle to verify the location of the wheel bearing noise. Did you locate the source of the wheel bearing noise? | Go to Step 6 | Go to Step 5 | |
| 5 | IMPORTANT: Support the vehicle by the lower control arms or the rear axle to prevent movement during wheel bearing/hub inspection. Mount and secure the J 8001 dial indicator. Ensure that the dial indicator contacts the vertical surface of the wheel as close as possible to the top wheel stud. Push and pull on the top of the tire in order to inspect the total travel indicated by the dial indicator. Is the measurement greater then the specified value? | 0.127 mm (0.005 in) | Go to Step 6 | System OK |
| 6 | Replace the wheel bearing. Refer to Front Wheel Hub, Bearing, and Seal Replacement (4WD) , Front Wheel Hub, Bearing, and Seal Replacement (RWD) . Did you complete the repair? | Go to Step 7 | ||
| 7 | Road test the vehicle to verify the repair. Does the vehicle operate normally? | System OK | Go to Step 3 |
| IMPORTANT |
|---|
| Support the vehicle by the lower control arms or the rear axle to prevent movement during wheel bearing/hub inspection. |
Wheel Bearings Diagnosis
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights can cause bottoming out over bumps, damage to the suspension components and symptoms similar to wheel alignment problems. Verify the trim heights when diagnosing suspension concerns and before inspecting the wheel alignment.
Perform the following before measuring the trim heights
- Ensure the vehicle is on a level surface, such as an alignment rack.
- Remove alignment rack floating plate pins.
- Set the tire pressures to specifications. Refer to «Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label»(/chevrolet/express-g2500/2013-2013/remont/hoistjack/#general-information) .
- Inspect the fuel level. Add additional weight if necessary to simulate a full tank.
- To ensure proper weight distribution verify the rear storage compartment is empty.
- Close the doors and hood.
Z Height Measurement
The Z height measurement determines the proper ride height for the front end of the vehicle. Vehicles equipped with torsion bars use an adjusting arm to adjust the Z height. Vehicles without torsion bars have no adjustment and could require replacement of suspension components.
| IMPORTANT | All dimensions are measured vertical to the ground. Trim heights should be within 12 mm (0.47 in) to be considered correct. |
- Place hand on the front bumper and jounce the front of the vehicle. Ensure that there is at least 38 mm (1.5 in) of movement while jouncing.
- Allow the vehicle to settle into position.
- Measure from the pivot bolt center line (2) down to the lower corner (5) of the steering knuckle (1) in order to obtain the Z height measurement (4).
- Repeat the jouncing operation 2 more times for a total of 3 times.
- Use the highest and lowest measurements to calculate the average height.
- The true Z height dimension number is the average of the highest and lowest measurements. Refer to «Trim Height Specifications»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__trim-height-specifications) .
Z Height Adjustment
- For vehicles equipped with a torsion bar suspension, turn the bolt (1) that contacts the torsion arm as needed. One revolution of the bolt (1) into the nut, increases the Z height by approximately 6.0 mm (0.2 in).
- For vehicles without torsion bars replace damaged or worn components as necessary.
- If these measurements are still out of specifications after adjustment or are not equipped with torsion bars, inspect for the following conditions: Sagging front suspension. Refer to «Front Spring Replacement»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#front-suspension-system) , or «Torsion Bar and Support Assembly Replacement»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#front-suspension-system__torsion-bar-and-support-assembly-replacement) . Collision damage
D Height Measurement
The D height measurement determines the proper ride height for the rear end of the vehicle. There is no adjustment procedure. Repair may require replacement of suspension components.
| IMPORTANT | All dimensions are measured vertical to the ground. Trim heights should be within 12 mm (0.47 in) to be considered correct. |
- Place hand on the rear bumper and jounce the rear of the vehicle. Ensure that there is at least 38 mm (1.5 in) of movement while jouncing.
- With the vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 in).
- Allow the vehicle to settle into position.
- Measure the D height by measuring the distance between the rear axle tube or rear axle bracket on vehicles with 7300 GVW rating and the frame.
- Repeat the jouncing operation 2 more times for a total of 3 times.
- Use the highest and lowest measurements to calculate the average height.
- The true D height dimension is the average of the highest and the lowest measurements. Refer to «Trim Height Specifications»(/chevrolet/express-g2500/2013-2013/remont/suspension-front/#suspension-system-general-diagnosis__trim-height-specifications) .
- If these measurements are out of specifications, inspect for the following conditions: Sagging rear leaf springs Refer to «Leaf Spring Replacement (1500/3500)»(/chevrolet/express-g2500/2013-2013/remont/suspension-rear/#rear-suspension-system) , «Leaf Spring Replacement (4500 Series)»(/chevrolet/express-g2500/2013-2013/remont/suspension-rear/#rear-suspension-system) . Collision damage
Special Tools
Illustration Tool Number/Description J 8001 Dial Indicator Set J 39570 Chassis Ear
See also:
• Diagnostic Starting Point - Vehicle
• General Description (Coil Spring)
• General Description (Torsion Bar)
• General Description
• General Description
• Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID Label
• Radial Tire Lead/Pull Correction
• Brake Rotor Thickness Variation Measurement
• Wheel Alignment Measurement
• Tire and Wheel Removal and Installation (6-Lug Wheel)
• Steering Linkage Outer Tie Rod Replacement
• Steering Linkage Outer Tie Rod Replacement
• Lower Control Arm Ball Joint Replacement (3500)
• Lower Control Arm Ball Joint Replacement (1500, 2500)
• Steering Gear Replacement (Rack and Pinion)
• Steering Gear Replacement (Recirculating Ball)
• Steering Column Replacement
• Vibration Analysis - Tire and Wheel
• Fastener Tightening Specifications
• Symptoms - Front Drive Axle
• Symptoms - Automatic Transmission
• Fastener Tightening Specifications
• Steering Linkage Inspection
• Lower Control Arm Replacement (RWD)
• Upper Control Arm Replacement
• Symptoms - Rear Drive Axle
• Fastener Tightening Specifications
• Shock Absorber Replacement
• Tire and Wheel Assembly Runout Measurement - On-Vehicle
• Front Wheel Hub, Bearing, and Seal Replacement (4WD)
• Torsion Bar and Support Assembly Replacement
• Ride Diagnosis
• Vehicle Leads/Pulls
• Body Leans or Sways in Corners
• Suspension Bottoms
• Memory Steer
• Noise Diagnosis - Front Suspension
• Noise Diagnosis - Rear Suspension
• Suspension Strut and Shock Absorber Testing - On Vehicle
• Wheel Bearings Diagnosis
• Symptoms - Suspension General Diagnosis
• Trim Height Inspection
• Trim Height Specifications