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Contents Section: Suspension Front All sections

Front Suspension System GMC Sierra 2500

Suspension Front 18 illustrations ~4452 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Hub and Bearing Assembly to Steering Knuckle Bolts (1500/2500/3500 Series)180 N.m133 lb ft
Lower Ball Joint Stud Nut (1500, 2500, 3500 Series)
First Pass50 N.m37 lb ft
Final PassAdditional 95 degrees
Lower Control Arm to Frame Nuts (1500 Series)175 N.m129 lb ft
Lower Control Arm to Frame Nuts (2500/3500 Series)
First Pass180 N.m133 lb ft
Final PassAdditional 60 degrees
Shock Absorber to Frame Nuts (2500/3500 Series)65 N.m48 lb ft
Shock Absorber Module to Frame Nuts (1500 Series)50 N.m37 lb ft
Shock Absorber Module to Lower Control Arm Bolt (1500 Series)50 N.m37 lb ft
Shock Absorber Tenon Nut (1500 Series)50 N.m37 lb ft
Shock Absorber to Lower Control Arm Bolts (2500/3500 Series)120 N.m89 lb ft
Stabilizer Shaft Insulator Clamp Bolts (1500/2500/3500 Series)50 N.m37 lb ft
Stabilizer Shaft Link Nuts (1500/2500/3500 Series)23 N.m17 lb ft
Torsion Bar Crossmember to Frame Bushing Bolt125 N.m92 lb ft
Upper Ball Joint Stud Nut (1500/2500/3500 Series)50 N.m37 lb ft
Upper Control Arm to Frame Nuts 1500 Series190 N.m140 lb ft
Upper Control Arm to Frame Nuts 2500/3500 Series260 N.m192 lb ft

Fastener Tightening Specifications

Adhesives, Fluids, Lubricants, and Sealers

ApplicationType of MaterialGM Part Number
USCanada
Stabilizer Shaft Link BoltThreadlocker Blue LOCTITE # 2421234538210953489

Adhesives, Fluids, Lubricants, and Sealers

Scheme 1

Scheme 1: Stabilizer Shaft Replacement (1500)
Scheme 1: Stabilizer Shaft Replacement (1500)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the front stabilizer shaft links. Refer to Stabilizer Shaft Link Replacement (2500, 3500) , Stabilizer Shaft Link Replacement (1500) . Remove the front stabilizer shaft insulators. Refer to Stabilizer Shaft Insulator Replacement .
1Front Stabilizer Shaft

Stabilizer Shaft Replacement (1500)

Scheme 2

Scheme 2: Stabilizer Shaft Replacement (2500, 3500)
Scheme 2: Stabilizer Shaft Replacement (2500, 3500)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the engine shield, if equipped. Refer to Engine Shield Replacement . Remove the stabilizer shaft links. Refer to Stabilizer Shaft Link Replacement (2500, 3500) , Stabilizer Shaft Link Replacement (1500) Remove the stabilizer shaft insulators. Refer to Stabilizer Shaft Insulator Replacement .
1Front Stabilizer Shaft

Stabilizer Shaft Replacement (2500, 3500)

Scheme 3

Scheme 3: Stabilizer Shaft Link Replacement (2500, 3500)
Scheme 3: Stabilizer Shaft Link Replacement (2500, 3500)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the engine shield, if equipped. Refer to Engine Shield Replacement . Loosen the stabilizer shaft insulator, if needed. Refer to Stabilizer Shaft Insulator Replacement .
1Stabilizer Shaft Link Retaining Nut CAUTION: Refer to Fastener Caution . Procedure Remove all traces of the original adhesive patch. Apply Threadlocker on the threads of the bolt. Refer to Adhesives, Fluids, Lubricants, and Sealers . Tighten 23 N.m (17 lb ft)
2Front Stabilizer Shaft Insulator (Qty: 4)
3Front Stabilizer Shaft Washer (Qty: 2)
4Front Stabilizer Shaft Spacer
5Front Stabilizer Shaft Washer
6Front Stabilizer Shaft Bolt
CAUTION
Refer to Fastener Caution .

Stabilizer Shaft Link Replacement (2500, 3500)

Scheme 4

Scheme 4: Stabilizer Shaft Link Replacement (1500)
Scheme 4: Stabilizer Shaft Link Replacement (1500)
CalloutComponent Name
Preliminary Procedure Remove the tire and wheel. Refer to Tire and Wheel Removal and Installation .
1Stabilizer Shaft Link Nut CAUTION: Refer to Fastener Caution . Procedure Remove all traces of the original adhesive patch. Apply Threadlocker on the threads of the bolts. Refer to Adhesives, Fluids, Lubricants, and Sealers . Tighten 23 N.m (17 lb ft)
2Stabilizer Shaft Link Bolt
3Stabilizer Shaft Link Washer (Qty: 2)
4Stabilizer Shaft Link Insulator (Qty: 4)
5Stabilizer Shaft Link Spacer
CAUTION
Refer to Fastener Caution .

Stabilizer Shaft Link Replacement (1500)

Scheme 5

Scheme 5: Stabilizer Shaft Insulator Replacement
Scheme 5: Stabilizer Shaft Insulator Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the engine shield, if equipped. Refer to Engine Shield Replacement .
1Stabilizer Shaft Clamp Bolt (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten 50 N.m (37 lb ft)
2Stabilizer Shaft Clamp
3Stabilizer Shaft Insulator TIP: Ensure the slit in the insulator is facing front of the vehicle when installed.
CAUTION
Refer to Fastener Caution .

Stabilizer Shaft Insulator Replacement

Lower Control Arm Ball Joint Replacement (1500)

Special Tools

  1. CH-49240 Ball Joint Crimper and Install Kit
  2. J-41805 Ball Joint Remover Install Kit

For equivalent regional tools, refer to Special Tools .

Removal Procedure

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the wheel drive shaft, if needed. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  3. Remove the steering knuckle from the vehicle. Refer to «Steering Knuckle Replacement»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  4. Using a hammer chisel, remove the locking tabs (1) from the ball joint body.
  5. Position the J-41805 kit (1) on the lower control arm.
  6. Using the J-41805 kit (1) and a shallow socket, remove the lower ball joint (2) from the control arm.

Installation Procedure

  1. Position the ball joint (1) in the lower control arm.
  2. Using the and a shallow socket J-41805 kit (2), CH-49240-3 (1), CH-49240-1 (4) and the CH-49240-2 (2), install the ball joint.
  3. Reverse the CH-49240-2 (3).
  4. Using the CH-41805 kit (2), CH-49240-3 (1), CH-49240-1 (4) and the CH-49240-2 (2), collapse the edge of the ball joint to create the lock tabs (5). Tighten the CH-49240-3 to 250 N.m (184 lb ft).
  5. Rotate the J-41805 kit (2) 180 degrees and repeat the process.
  6. Install the wheel drive shaft, if needed. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  7. Install the steering knuckle in the vehicle. Refer to «Steering Knuckle Replacement»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  8. Install the lower ball joint stud nut and tighten to: First Pass: 50 N.m (37 lb ft) Final Pass: additional 95 degrees
  9. Remove the supports and lower the vehicle.

Lower Control Arm Ball Joint Replacement (2500, 3500)

Special Tools

  1. CH 49240 Ball Joint Crimper and Install Kit
  2. J 41805 Ball Joint remover/Installer

For equivalent regional tools, refer to Special Tools .

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the knuckle from the vehicle. Refer to «Steering Knuckle Replacement»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  3. Using a hammer and a chisel, remove the lock tabs (1) from the lower ball joint.
  4. Using the J 41805 remover/installer (1) and the appropriate adapter, remove the lower ball joint (2).
  1. Position the lower ball joint (1) in the lower control arm.
  2. Align the lower ball joint grease fitting (1) with the channel (2) in the lower control arm
  3. Using the J 41805 remover/installer (1), the appropriate adapter (3), and the CH 49240 install Kit (2), install the lower ball joint.
  4. Ensure that the ball joint (2) is fully seated against the lower control arm (1).
  5. Using a hammer and a punch, created the lock tabs (1) for the lower ball joint.
  6. Install the knuckle. Refer to «Steering Knuckle Replacement»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  7. Install the lower ball joint stud nut and tighten to: First Pass: 50 N.m (37 lb ft) Final Pass: additional 95 degrees
  8. Remove the support and lower the vehicle.

Scheme 6

Scheme 6: Steering Knuckle Replacement
Scheme 6: Steering Knuckle Replacement
CalloutComponent Name
Preliminary procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel. Refer to Tire and Wheel Removal and Installation . Remove the wheel bearing/hub assembly from the steering knuckle. Refer to Front Wheel Hub, Bearing, and Seal Replacement (1500) , Front Wheel Hub, Bearing, and Seal Replacement (2500, 3500) .
1Steering Knuckle Procedure Remove the outer tie rod end from the steering knuckle. Refer to Steering Linkage Outer Tie Rod Replacement . Separate the upper control arm from the steering knuckle. Refer to Upper Control Arm Replacement (1500) , Upper Control Arm Replacement (2500, 3500) . Separate the lower control arm from the steering knuckle. Refer to Lower Control Arm Replacement (2500, 3500) , Lower Control Arm Replacement (1500) . Verify the wheel alignment. Refer to Wheel Alignment Specifications (1500) , Wheel Alignment Specifications (2500 and 3500) .

Steering Knuckle Replacement

Upper Control Arm Replacement (2500, 3500)

Special Tools

J 42188-B Ball Joint Separator

For equivalent regional tools, refer to Special Tools

  1. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  2. Lower the vehicle and support the lower control arm.
  3. Remove the front shock absorber. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  4. Loosen the upper ball joint nut, but DO NOT remove.
  5. Using the J 42188-B separator, remove the upper control arm from the steering knuckle.
  6. Remove the J 42188-B separator and the upper ball joint nut. Discard the nut and replace with NEW only.
  7. Remove the upper control arm nuts (1), (6) and the adjustment cams (2), (5).
  8. Remove the adjuster bolts (3), (4).
  9. Remove the upper control arm (1) from the frame.
  1. Position the upper control arm (1) in the frame.
  2. Install the upper control arm bolts (3), (4) and the adjusters (2), (5).
  3. Install the upper control arm nuts (1), (6) and tighten to 260 N.m (192 lb ft).
  4. Install the upper control arm to the steering knuckle.
  5. Install the NEW nut to the upper ball joint stud and tighten to 50 N.m (37 lb ft).
  6. Install the front shock absorber. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  7. Raise the vehicle and remove the support for the lower control arm.
  8. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  9. Verify the wheel alignment. Refer to «Wheel Alignment Specifications (1500)»(/gmc/sierra-2500/2012-2012/remont/wheel-alignment/#wheel-alignment-system__wheel-alignment-specifications-1500) , «Wheel Alignment Specifications (2500 and 3500)»(/gmc/sierra-2500/2012-2012/remont/wheel-alignment/#wheel-alignment-system__wheel-alignment-specifications-2500-and-3500) .

Scheme 7

Scheme 7: Upper Control Arm Replacement (1500)
Scheme 7: Upper Control Arm Replacement (1500)
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the front tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Upper Ball Joint Stud Nut CAUTION: Refer to Fastener Caution . Procedure Use a suitable jack stand, support the lower control arm. Using the CH 42188-B separator, separate the ball joint from the steering knuckle. Remove and discard the upper arm ball joint stud nut. Replace with NEW only. Remove the wheel speed sensor wiring harness from the knuckle. Refer to Front Wheel Speed Sensor Replacement . Tighten 50 N.m (37 lb ft) Special Tools CH 42188-B Ball Joint Separator For equivalent regional special tools, refer to Special Tools .
2Upper Control Arm Nut (Qty: 2) Tighten 190 N.m (140 lb ft)
3Upper Control Arm Alignment Cam (Qty: 4)
4Upper Control Arm Bolt (Qty: 2)
5Upper Control Arm Procedure Verify wheel alignment. Refer to Wheel Alignment Specifications (1500) , Wheel Alignment Specifications (2500 and 3500) .
CAUTION
Refer to Fastener Caution .

Upper Control Arm Replacement (1500)

Lower Control Arm Replacement (2500, 3500)

Special Tools

  1. CH 43631 Ball Joint Separator
  2. J 45851 Ball Joint Separator Protector Adapters

For equivalent regional tools, refer to Special Tools .

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove the stabilizer shaft links from the lower control arm. Refer to «Stabilizer Shaft Link Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) , «Stabilizer Shaft Link Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  4. Remove the torsion bars. Refer to «Torsion Bar and Support Assembly Replacement (Bushing Style)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system__torsion-bar-and-support-assembly-replacement) .
  5. Remove the front shock absorber from the lower control arm. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  6. Remove the wheel drive shaft, if needed. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  7. Remove and discard the lower ball joint retaining nut (1). Replace with NEW only.
  8. Using the CH 43631 separator (1) and the J 45851 adapters (2), remove the lower ball joint from the steering knuckle.
  9. Remove the front lower control arm nut (1) and bolt (2).
  10. Remove the lower control rear nut (1) and bolt (2).
  11. Remove the lower control arm (3).
  1. Position the lower control arm (3) in the frame.
  2. Install the lower control arm rear bolt (2) and nut (1) and hand tighten.
  3. Install the lower control arm front bolt (2) and nut (1) and hand tighten.
  4. Before tighten the lower control nuts to the specified torque, perform the following to ensure the proper trim height settings: Support the lower control arm. Using an appropriate hydraulic jack, raise the lower control arm until just contacts both jumper bumpers.
  5. Tighten the front and rear lower control arm mounting nuts: First Pass 180 N.m (133 lb ft). Final Pass additional 60 degrees.
  6. Install the lower ball joint in the steering knuckle.
  7. Install the NEW lower ball joint nut (1) and tighten to: First Pass 50 N.m (37 lb ft). Final Pass additional 95 degrees.
  8. Install the front shock absorber to the lower control arm. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  9. Install the wheel drive shaft, if removed. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  10. Install the torsion bars. Refer to «Torsion Bar and Support Assembly Replacement (Bushing Style)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system__torsion-bar-and-support-assembly-replacement) .
  11. Install the stabilizer shaft links to the lower control arm. Refer to «Stabilizer Shaft Link Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) , «Stabilizer Shaft Link Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  12. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  13. Remove the supports and lower the vehicle.
  14. Align the front end. Refer to «Wheel Alignment Measurement»(/gmc/sierra-2500/2012-2012/remont/wheel-alignment/#wheel-alignment-system__wheel-alignment-measurement) .

Lower Control Arm Replacement (1500)

Special Tools

  1. CH 3631 Ball Joint Separator
  2. J 45851 Ball Joint Separator Protector Adapters

For equivalent regional tools, refer to Special Tools .

Note. For vehicles equipped with the aluminum lower control arm, the ball joint is NOT service separately. If the ball joint in the aluminum lower control arm is found to have excessive wear and is damaged, replace the lower control arm as an assembly.

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove the stabilizer shaft link from the lower control arm. Refer to «Stabilizer Shaft Link Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) , «Stabilizer Shaft Link Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  4. Remove the wheel drive shaft, if equipped. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  5. Using mechanics wire or equivalent, support the knuckle assembly and upper control arm.
  6. Remove and discard the lower ball joint retaining nut (1).
  7. Remove the lower shock bolts from the lower control arm. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  8. Using the CH 3631 ball joint separator (1) and the J 45851 ball joint separator protector adapters (2), remove the lower ball joint from the steering knuckle.
  9. Remove the lower control arm nuts (1) and washers (2).
  10. Remove the control arm bolts (3).
  11. Remove the control arm (4).
  1. Install the lower control arm (4).
  2. Install the lower control arm bolts (3).
  3. Install the washers (2).
  4. Install the lower control arm retaining nuts (1) and tighten to 175 (129 lb ft).
  5. Install the lower ball joint in the steering knuckle.
  6. Install the lower ball stud nut (1) and tighten to: First Pass 50 (37 lb ft) Final Pass additional 95 degrees
  7. Install the lower shock absorber bolts to the lower control arm. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  8. Remove the support for the steering knuckle and upper control arm.
  9. Install the wheel drive shaft, if equipped. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  10. Install the stabilizer shaft link to the lower control arm. Refer to «Stabilizer Shaft Link Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) , «Stabilizer Shaft Link Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  11. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  12. Remove the support and lower the vehicle.
  13. Align the front end. Refer to «Wheel Alignment Measurement»(/gmc/sierra-2500/2012-2012/remont/wheel-alignment/#wheel-alignment-system__wheel-alignment-measurement) .

Scheme 8

Scheme 8: Jounce Bumper Replacement (2500, 3500)
Scheme 8: Jounce Bumper Replacement (2500, 3500)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle
1Front Lower Control Arm Bumper (Qty: 2)

Jounce Bumper Replacement (2500, 3500)

Wheel Stud Replacement

Tools Required

J 43631 Ball Joint Remover

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove the brake rotor. Refer to «Front Brake Rotor Replacement (JD9, JF3, JF7, JG4)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J95)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J90, J96)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) .
  4. Use the J 43631 ball joint remover to press the stud from the wheel bearing/hub.
  1. Install a new stud. Use washers and a wheel nut and pull the new stud into the hub.
  2. Install the brake rotor. Refer to «Front Brake Rotor Replacement (JD9, JF3, JF7, JG4)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J95)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J90, J96)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) .
  3. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  4. Lower the vehicle.
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Remove the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove the brake rotor. Refer to «Front Brake Rotor Replacement (JD9, JF3, JF7, JG4)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J95)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J90, J96)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) .
  4. Remove the wheel speed sensor from the wheel hub and bearing. Refer to «Front Wheel Speed Sensor Replacement»(/gmc/sierra-2500/2012-2012/remont/anti-locktraction-control/#antilock-brake-system-non-hybrid-less-than-3900-kg-8600-lb-gvw)
  5. Remove the wheel driveshaft nut retaining cover.
  6. Wrap shop towel around the inner and outer wheel drive shaft boot.
  7. Separate the wheel driveshaft assembly from the wheel hub and bearing. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500) .
  8. Remove the wheel hub and bearing mounting bolts.
  9. Remove the wheel hub and bearing and splash shield from the vehicle.
  10. Remove the O-ring seal from the steering knuckle bore.
  11. Clean and inspect the O-ring seal.
  12. Replace the seal if the following conditions exist: Nicks Cuts Dry or brittle Compression set
  1. Clean all corrosion or contaminates from the steering knuckle bore and the hub and bearing assembly.
  2. Lubricate the steering knuckle bore with wheel bearing grease or the equivalent.
  3. Install the O-ring to the steering knuckle.
  4. Install the wheel speed sensor to the wheel hub and bearing. Refer to «Front Wheel Speed Sensor Replacement»(/gmc/sierra-2500/2012-2012/remont/anti-locktraction-control/#antilock-brake-system-non-hybrid-less-than-3900-kg-8600-lb-gvw)
  5. Install the wheel hub and bearing and splash shield to the vehicle.
  6. Install the wheel hub and bearing mounting bolts to 180 N.m (133 lb ft).
  7. Install the nut and washer retaining the wheel drive shaft assembly to the wheel hub and bearing. Refer to «Wheel Drive Shaft Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-1500) , «Wheel Drive Shaft Replacement (2500/3500)»(/gmc/sierra-2500/2012-2012/remont/axle-shafts/#wheel-drive-shafts__wheel-drive-shaft-replacement-25003500)
  8. Install the brake rotor. Refer to «Front Brake Rotor Replacement (JD9, JF3, JF7, JG4)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J95)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) , «Front Brake Rotor Replacement (J90, J96)»(/gmc/sierra-2500/2012-2012/remont/mechanical-hydraulic/#disc-brake-system) .
  9. Install the tire and wheel. Refer to «Tire and Wheel Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/wheel-tire-system/#tires-and-wheels) .
  10. Lower the vehicle.

Scheme 9

Scheme 9: Front Wheel Hub, Bearing, and Seal Replacement (1500)
Scheme 9: Front Wheel Hub, Bearing, and Seal Replacement (1500)
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the brake rotor. Refer to Front Brake Rotor Replacement (JD9, JF3, JF7, JG4) , Front Brake Rotor Replacement (J95) , Front Brake Rotor Replacement (J90, J96) . Remove the speed sensor, if equipped. For hybrid vehicles, refer to Front Wheel Speed Sensor Replacement . For non-hybrid vehicles, refer to Front Wheel Speed Sensor Replacement . For vehicles equipped with 4WD, remove the wheel drive shaft from the wheel bearing and hub assembly. Refer to Wheel Drive Shaft Replacement (1500) , Wheel Drive Shaft Replacement (2500/3500) .
1Wheel Bearing and Hub Bolt (Qty: 3) CAUTION: Refer to Fastener Caution . Tighten 180 N.m (133 lb ft)
2Wheel Hub and Bearing Assembly TIP: New wheel bearing comes with a wheel speed sensor installed.
CAUTION
Refer to Fastener Caution .

Front Wheel Hub, Bearing, and Seal Replacement (1500)

Torsion Bar and Support Assembly Replacement (Bushing Style)

Special Tools

CH 48809 Torsion Bar Unloading/Loading Tool

For equivalent regional tools, refer to Special Tools .

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Before removing the torsion bar support, measure the distance from the adjuster nut (1) and the head of the adjuster bolt (2). Record the measurement.
  3. Remove the torsion bar adjuster bolt (2) from the adjuster nut (1) and allow the adjuster arm to rest on in the crossmember.
  4. Using the CH 48809 tool (1), increase the tension on the adjustment arm until the load is removed from the adjuster nut.
  5. Remove the adjust nut (2) from the crossmember.
  6. Using the CH 48809 tool, unload the torsion bar.
  7. Remove the adjustment arm (3) by sliding the torsion bar forward.
  8. Remove the torsion bar crossmember bolt (1).
  9. Remove the torsion bar support (1) from the frame.
  10. Remove the torsion bar (1) from the vehicle.
  1. Position the torsion bar (1) in the lower control arm.
  2. Install the torsion bar support (1) in the frame.
  3. Install the torsion bar crossmember bolt (1) and tighten to 125 N.m (92 lb ft).
  4. Install the adjustment arm (3) in the crossmember.
  5. Install the torsion bar into the adjustment arm until the torsion bar is fully seated.
  6. Using the CH 48809 tool (1), increase the tension on the adjustment arm to load the torsion bar.
  7. Install the adjuster nut in the crossmember.
  8. Unload the CH 48809 tool (1) to allow adjuster arm to rest on the adjuster and remove the CH 48809 tool (1) from the crossmember.
  9. Install the adjuster bolt (2) in the adjuster nut (1) and turn the adjuster bolt (2) until it contacts the adjuster arm.
  10. Turn the adjuster bolt until the length of the adjuster bolt is the same distance from the adjuster bolt head to the adjuster nut prior to removing the bolt.
  11. Remove the safety stands and lower the vehicle.
  12. Measure the Z height. Refer to «Trim Height Inspection»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#suspension-system-general-diagnosis__trim-height-inspection) .

Scheme 10

Scheme 10: Torsion Bars Bushing Replacement
Scheme 10: Torsion Bars Bushing Replacement
CalloutComponent Name
Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the torsion bars. Refer to Torsion Bar and Support Assembly Replacement (Bushing Style) .
1Front Suspension Torsion Bar Bushing Procedure When installing the NEW bushing, ensure that the inner slot is horizontal. Using the appropriate bushing remover/installer, remove the bushing. After installing the bushing, peen the bushing in three places 120 degrees apart from each other. Measure the trim height. Refer to Trim Height Inspection .

Torsion Bars Bushing Replacement

Strut and Shock Absorber Inspection (Shock Absorber)

Note. The shock absorber assembly DOES NOT have to be removed from the vehicle to perform the following inspection procedure.

Note. A light film of oil on the top portion of the lower shock absorber tube is normal. DO NOT replace the shock absorber for this condition.

Scheme 11

Scheme 11: Strut and Shock Absorber Inspection (Shock Absorber)
Scheme 11: Strut and Shock Absorber Inspection (Shock Absorber)

Condition 1

Oil or fluid residue only on the bottom or top of the shock absorber and not originating from the shaft seal, is not a shock absorber related problem. DO NOT replace the shock absorber, look for other external leaks.

Condition 2

Light film/residue on approximately 1/3 (a) or less of the lower shock tube (A) and originating from the shaft seal, is a NORMAL condition. DO NOT replace the shock absorber.

Condition 3

Oil drip or trail down the lower shock tube and originating from the shaft seal, is an ABNORMAL condition. Replace the shock absorber.

Condition 4

An extreme wet film of oil covering more than 1/3 (b) of the lower shock tube and originating from the shaft seal (B), is an ABNORMAL condition. Replace the shock absorber. Refer to Shock Absorber Replacement (2500, 3500) , Shock Absorber Replacement (1500) .

Inspection

  1. Verify the customer's concern is present. If the concern is present, continue to the next step. If the concern is not present, then the vehicle is operating normally.
  2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  3. Visually inspect each of the shock absorbers for external fluid leaks. Refer to the following conditions 1, 2, 3, and 4 for visual inspection. If conditions 1 or 2 are found, continue to step 4. If conditions 3 or 4 are found, replace shock absorber. Refer to «Shock Absorber Replacement (2500, 3500)»(/gmc/sierra-2500/2012-2012/remont/suspension-rear/#rear-suspension-system) , «Shock Absorber Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/suspension-rear/#rear-suspension-system) .
  4. If equipped with electronic suspension control system, ensure that the system is working properly. Refer to Diagnostic Starting Point - Electronic Suspension Control.
  5. Use your hands in order to lift up and push down on each corner of the vehicle 3 times. Remove your hands from the vehicle. If the corner motion exceeds 2 cycles, replace the shock absorber. If the shock absorber does not exceed 2 cycles, NO repair is necessary.

Strut and Shock Absorber Inspection (Coil Over Shock)

Note. The coil over shock assembly DOES NOT have to be removed from the vehicle to perform the following inspection procedure.

Note. A light film of oil on the top portion of the shock absorber tube is normal. DO NOT replace the shock absorber for this condition.

Scheme 12

Scheme 12: Strut and Shock Absorber Inspection (Coil Over Shock)
Scheme 12: Strut and Shock Absorber Inspection (Coil Over Shock)

Condition 1

Oil or fluid residue only on the bottom of the lower shock absorber tube or other coil over shock absorber and originating from the shaft seal, is not a shock absorber related problem. DO NOT replace the shock absorber, look for other external leaks.

Condition 2

Light film/residue on the shock absorber tube, but not on the spring seat and originating from the shaft seal, is a NORMAL condition. DO NOT replace the shock absorber.

Condition 3

Oil drip or trail down the shock absorber tube and originating from the shaft seal, is an ABNORMAL condition. Replace the shock absorber.

Condition 4

An extreme wet film of oil covering the shock absorber tube and pooling in the spring seat and originating from the shaft seal, is an ABNORMAL condition. Replace the shock absorber.

Inspection

  1. Verify the customer's concern is present. If the concern is present, continue to the next step. If the concern is not present, then the vehicle is operating normally.
  2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  3. Visually inspect each of the shock absorbers for external fluid leaks. Refer to the following conditions 1, 2, 3, and 4 for visual inspection. If conditions 1 or 2 are found, continue to step 4. If conditions 3 or 4 are found, replace shock absorber. Refer to Shock Absorber Replacement.
  4. If equipped with electronic suspension control system, ensure that the system is working properly. Refer to Diagnostic Starting Point-Electronic Suspension Control.
  5. Use your hands in order to lift up and push down on each corner of the vehicle 3 times. Remove your hands from the vehicle. If the corner motion exceeds 2 cycles, replace the shock absorber. If the shock absorber does not exceed 2 cycles, NO repair is necessary.

Scheme 13

Scheme 13: Shock Absorber and Spring Removal and Installation
Scheme 13: Shock Absorber and Spring Removal and Installation
CalloutComponent Name
Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the front tire and wheel assembly. Refer to Tire and Wheel Removal and Installation . Disconnect the outer tie rod from the steering knuckle. Refer to Steering Linkage Outer Tie Rod Replacement .
1Shock Absorber Module Bolt (Qty: 2) Procedure Support the lower control arm. CAUTION: Do not use air powered tools in order to disassemble or assemble any vehicle component. Bolt torques are vital to diagnosis. You can detect bolt torques only when using hand tools. Improper bolt torques can contribute to vehicle repair problems. CAUTION: Refer to Fastener Caution . Tighten 50 N.m (37 lb ft)
2Shock Absorber Module Nut (Qty: 3) Tighten 50 N.m (37 lb ft)
3Shock Absorber Module Procedure If removing the shock module in order to service the components, refer to Shock Absorber, Shock Absorber Component, or Spring Replacement . For the proper disposal procedure of the shock absorber, refer to Shock Absorber Disposal .
CAUTION
Do not use air powered tools in order to disassemble or assemble any vehicle component. Bolt torques are vital to diagnosis. You can detect bolt torques only when using hand tools. Improper bolt torques can contribute to vehicle repair problems.
CAUTION
Refer to Fastener Caution .

Shock Absorber and Spring Removal and Installation

Shock Absorber, Shock Absorber Component, or Spring Replacement

Special Tools

CH 48845 Spring Compressor

For equivalent regional tools, refer to Special Tools

  1. Install the front shock absorber assembly in the CH 48845 compressor.
  2. Position the shock absorber (2) in the upper retaining bracket of the CH 48845 compressor (1) so the shock absorber will be centered.
  3. Using the CH 48845 compressor (1), compress the front spring (2).
  4. Using the appropriate size wrench, hold the shock absorber shaft.
  5. Using the appropriate tool, remove and discard the shock absorber nut (1).
  6. Remove the front lower shock absorber (2) and the front spring lower insulator (1).
  7. Remove the front suspension strut mount (1), front spring upper seat (2), front suspension strut bumper (3), front spring upper insulator (4), and the front suspension spring (5) from the spring compressor.
  1. Assemble the front suspension strut mount (1), front spring upper seat (2), front suspension strut bumper (3), front spring upper insulator (4), and the front suspension spring (5) in the spring compressor.
  2. Align the spring seat stop (3), the outboard stud (1), and the center of the lower strut mount (4). The notch in the spring seat (2) should be just to the right of the outboard stud.
  3. Position the shock absorber (2) in the upper retaining bracket of the CH 48845 compressor (1) so the shock absorber will be centered.
  4. Using the CH 48845 compressor (1), compress the front spring (2).
  5. Using the appropriate size wrench, hold the shock absorber shaft.
  6. Install the shock absorber nut (1) and tighten to 50 N.m (37 lb ft).
  7. Remove the shock absorber assembly from the spring compressor
  8. Install the shock absorber in the vehicle. Refer to «Shock Absorber and Spring Removal and Installation»(/gmc/sierra-2500/2012-2012/remont/suspension-front/#front-suspension-system) .
  1. Raise the vehicle enough to place a floor jack under the lower control arm.
  2. Reposition the engine splash shield between the frame and the inner wheel house to gain access to the upper shock absorber nuts.
  3. Remove the upper front shock absorber nuts (1).
  4. Remove the lower front shock absorber nut (1) and bolt (2).
  5. Remove the front shock absorber (1) from the vehicle.
  1. Position the front shock absorber (1) in the frame.
  2. Install the lower front shock absorber nut (1) and bolt (2) and tighten the bolt to 120 N.m (89 lb ft).
  3. Install the upper front shock absorber nuts and tighten to 65 N.m (48 lb ft).
  4. Reposition the engine splash shield.
  5. Remove the support from the lower control arm.
  6. Lower the vehicle.

Shock Absorber Disposal

WARNINGGas charged shock absorbers contain high pressure gas. Do not remove the snap ring from inside the top of the tube. If the snap ring is removed, the contents of the shock absorber will come out with extreme force which may result in personal injury.
WARNINGTo prevent personal injury, wear safety glasses when centerpunching and drilling the shock absorber. Use care not to puncture the shock absorber tube with the centerpunch.
  1. Make an indentation 10 mm (0.4 in) from the bottom (4) of the tube (3) using a centerpunch.
  2. Clamp the shock absorber in a vise horizontally with the shock absorber rod (1) completely extended.
  3. Drill a hole in the shock absorber at the centerpunch (4) using a 5 mm (3/16 in) drill bit. Gas or a gas/oil mixture will exhaust when the drill bit penetrates the shock absorber. Use shop towels in order to contain the escaping oil.
  4. Make an indentation in the middle (2) of the tube (3) with a centerpunch.
  5. Drill a second hole in the shock absorber at the centerpunch (2) using a 5 mm (3/16 in) drill bit. Oil will exhaust when the drill bit penetrates the shock absorber. Use shop towels in order to contain the escaping oil.
  6. Remove the shock absorber from the vise. Hold the shock absorber over a drain pan horizontally with the holes down. Move the rod (1) in and out of the tube (3) to completely drain the oil from the shock absorber.

General Description

The front suspension allows each wheel to compensate for changes in the road surface without affecting the opposite wheel. Each wheel independently connects to the frame with a steering knuckle, ball joint assemblies, and upper and lower control arms.

Two tie rods connect to the steering arms on the knuckles and to a steering gear.

Rear wheel drive models have a front suspension that consists of the following components

  1. Control arms
  2. Stabilizer shaft
  3. Shock/Coil spring modules

The upper part of each Shock/Coil spring module bolts to the frame. Three insulators, a mounting plate and a nut secure the coil spring to the shock housing. Two bolts secure the lower part of the shock module to the lower control arm.

A spring steel stabilizer shaft controls the side roll of the front suspension. This shaft is mounted in rubber insulators that are held by clamps to the frame side rails. The ends of the stabilizer shaft connect to the lower control arms with link assemblies.

The upper ball joint assembly is integrated into the upper control arm. The assembly attaches to the steering knuckle with a prevailing torque nut.

The lower ball joint assembly is integrated into the control arm. The assembly attaches to the steering knuckle with a prevailing torque nut.

The upper and the lower control arms have pressed-in bushings. The bolts pass through the bushings and join the arms to the frame.

Ball joint assemblies have rubber grease seals. These seals prevent the entry of moisture and dirt. This prevents damage to the bearing surfaces.

Four-wheel drive models have a front suspension that consists of the following components

  1. Control arms
  2. Stabilizer shaft
  3. Shock module/Shock absorbers
  4. Coil Springs (1500 series)
  5. Torsion bars (2500, 3500 series)

The upper part of each shock absorber (2500, 3500 series) extends through a frame bracket. Two insulators and a nut secure the upper part of the shock to the frame. A through bolt secures the lower part of the shock to the lower control arm.

The upper part of each shock module (1500 series) attaches to the frame by 3 nuts. The lower part of the shock module attaches to the lower control arm by 2 bolts.

A spring steel stabilizer shaft controls the side roll of the front suspension. This shaft is mounted in rubber insulators that are held by clamps to the frame side rails. The ends of the stabilizer shaft connect to the lower control arms with link assemblies.

The front end of the torsion bar attaches to the lower control arm. The rear of the torsion bar mounts into an adjustable arm at the torsion bar crossmember. This arm adjustment controls the vehicle trim height.

Both RWD and 4WD models have sealed front wheel bearings. These bearings are pre-adjusted and need no lubrication.

Special Tools

Illustration Tool Number/Description CH-3631 J-43631 Ball Joint Remover CH-42188-B J-42188-B Ball Joint Separator CH-48809 Torsion Bar Loading/Unloading Tool CH-48845 Front Spring Compressor CH-49240 Ball Joint Crimp and Install Tool J-41805 Ball Joint Remover/Installer J-45851 Ball Joint Separator Protector Adapters

Scheme 14

Scheme 14: Special Tools
Scheme 14: Special Tools

Scheme 15

Scheme 15
Scheme 15

Scheme 16

Scheme 16
Scheme 16

Scheme 17

Scheme 17
Scheme 17

Scheme 18

Scheme 18
Scheme 18

See also:
• Lifting and Jacking the Vehicle
• Engine Shield Replacement
• Fastener Caution
• Tire and Wheel Removal and Installation
• Special Tools
• Wheel Drive Shaft Replacement (1500)
• Wheel Drive Shaft Replacement (2500/3500)
• Steering Linkage Outer Tie Rod Replacement
• Wheel Alignment Specifications (1500)
• Wheel Alignment Specifications (2500 and 3500)
• Front Wheel Speed Sensor Replacement
• Wheel Alignment Measurement
• Front Brake Rotor Replacement (JD9, JF3, JF7, JG4)
• Front Wheel Speed Sensor Replacement
• Front Wheel Speed Sensor Replacement
• Trim Height Inspection
• Shock Absorber Replacement (2500, 3500)
• Stabilizer Shaft Link Replacement (2500, 3500)
• Adhesives, Fluids, Lubricants, and Sealers
• Upper Control Arm Replacement (2500, 3500)
• Lower Control Arm Replacement (2500, 3500)
• Lower Control Arm Replacement (1500)
• Special Tools
• Torsion Bar and Support Assembly Replacement (Bushing Style)
• Shock Absorber, Shock Absorber Component, or Spring Replacement
• Shock Absorber Disposal

More articles — Suspension