GM Service Manual Online
For 1990-2009 cars only

Front Suspension Crossmember Replacement Independent

Removal Procedure

For control arms and components, refer to

Lower Control Arm and Components (Independent Suspension)


Object Number: 175323  Size: LF
(1)Bumper
(2)Steering Knuckle
(3)Coil Spring
(4)Air Cylinder
(5)Lower Ball Joint Nut
(6)Cotter Pin
(7)Lower Control Arm
(8)Lower Ball Joint
(9)Lower Ball Joint Grease Fitting
(10)Stabilizer Shaft to Lower Control Arm Clamp Nut
(11)Stabilizer Shaft Bushing
(12)Stabilizer Shaft to Lower Control Arm Clamp
(13)Stabilizer Shaft to Lower Control Arm Clamp Bolt
(14)Lower Control Arm Seal Grease Fitting
(15)Lower Control Arm Rear Bushing
(16)Pivot Shaft Seal
(17)Pivot Shaft U-bolts
(18)Lower Control Arm Pivot Shaft
(19)Pivot Shaft Brackets
(20)Pivot Shaft Seal
(21)Lower Control Arm Front Bushing
(22)Lower Control Arm Seal Grease Fitting
(23)Pivot Shaft Bracket Nut
(24)Pivot Shaft Bracket Rivet
(25)Pivot Shaft Bolt
(26)Pivot Shaft Nut
(27)Pivot Shaft
or

Upper Control Arm and Components (Independent Suspension)


Object Number: 175324  Size: LF
(1)Upper Ball Joint
(2)Upper Ball Joint Rivet
(3)Upper Ball Joint Grease Fitting
(4)Upper Ball Joint Nut
(5)Cotter Pin
(6)Upper Control Arm Front Seal Grease Fitting
(7)Upper Control Arm Front Bushing
(8)Upper Control Arm Front Seal
(9)Upper Control Arm
(10)Upper Control Arm Pivot Shaft Nuts
(11)Upper Control Arm Rear Seal
(12)Upper Control Arm Rear Bushing
(13)Upper Control Arm Rear Seal Grease Fitting
(14)Upper Control Arm Pivot Shaft Spacer
(15)Shim Pack
(16)Upper Control Arm Frame Bracket
(17)Upper Control Arm Pivot Shaft Bolt
(18)Reinforcement to Frame Washer
(19)Reinforcement to Frame Bolt
(20)Reinforcement
(21)Frame Bracket Washer
(22)Frame bracket Nut
(23)Shim Pack
(24)Upper Control Arm Pivot Shaft Spacer
(25)Upper Control Arm Pivot Shaft
.

The front suspension and frame crossmember can be removed or installed as a unit if extensive service is required.

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Raise the vehicle on a hoist. Support the vehicle with suitable safety stands placed at the frame side rails.
  3. Lower the hoist.
  4. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  5. Remove the front brake hose clip from both of the upper control arms.
  6. Disconnect the brake hoses from the calipers.
  7. 6.1. For commercial vehicles, refer to Front Brake Hose Replacement in Hydraulic Brakes.
    6.2. For motorhome vehicles, refer to Front Brake Hose Replacement in Hydraulic Brakes.
  8. Clean the area adjacent to the brake hose fittings.
  9. Discard the special washers (2 on each hose), and cover the disconnected ends of each hose with suitable material.
  10. Disconnect the tie rod ends from the steering knuckle. Refer to Tie Rod Replacement in Steering Linkage.

  11. Object Number: 175282  Size: SH
  12. Remove the nuts (3), the bolts (2), and the brackets (1).
  13. Remove the front stabilizer shaft from the lower control arms.

  14. Object Number: 175279  Size: SH
  15. Remove the nut, the washer, and the bolt.
  16. Remove the shock absorbers from the lower control arms.
  17. Notice: Failure to disconnect the brake line clips from the suspension unit will result in severe damage to the brake line when the unit is lowered from the vehicle.

  18. Remove the brake line clip bolts from the front suspension crossmember.
  19. Remove the suspension crossmember from the engine mounts. Refer to Engine Mount Replacement or Engine Mount Replacement or Engine Mount Replacement or Engine Mount Replacement in Engine Mechanical.

  20. Object Number: 175300  Size: SH
  21. Remove the suspension crossmember (11) from the frame rail (4).
  22. 16.1. Raise the hoist in order to support the suspension crossmember.
    16.2. Support the engine.
    16.3. These must be done before the suspension unit is lowered from the vehicle.
  23. Remove the upper control arm bracket to frame side rail nuts (13), the washers (5), and the bolts (6).
  24. Remove the suspension and crossmember unit bolts (10), the washers (9), and the nuts (8). When removing the suspension and crossmember unit, lower the suspension and crossmember unit in order to bring the unit clear of the vehicle.

Installation Procedure

For control arms and components, refer to

Lower Control Arm and Components (Independent Suspension)


Object Number: 175323  Size: LF
(1)Bumper
(2)Steering Knuckle
(3)Coil Spring
(4)Air Cylinder
(5)Lower Ball Joint Nut
(6)Cotter Pin
(7)Lower Control Arm
(8)Lower Ball Joint
(9)Lower Ball Joint Grease Fitting
(10)Stabilizer Shaft to Lower Control Arm Clamp Nut
(11)Stabilizer Shaft Bushing
(12)Stabilizer Shaft to Lower Control Arm Clamp
(13)Stabilizer Shaft to Lower Control Arm Clamp Bolt
(14)Lower Control Arm Seal Grease Fitting
(15)Lower Control Arm Rear Bushing
(16)Pivot Shaft Seal
(17)Pivot Shaft U-bolts
(18)Lower Control Arm Pivot Shaft
(19)Pivot Shaft Brackets
(20)Pivot Shaft Seal
(21)Lower Control Arm Front Bushing
(22)Lower Control Arm Seal Grease Fitting
(23)Pivot Shaft Bracket Nut
(24)Pivot Shaft Bracket Rivet
(25)Pivot Shaft Bolt
(26)Pivot Shaft Nut
(27)Pivot Shaft
or

Upper Control Arm and Components (Independent Suspension)


Object Number: 175324  Size: LF
(1)Upper Ball Joint
(2)Upper Ball Joint Rivet
(3)Upper Ball Joint Grease Fitting
(4)Upper Ball Joint Nut
(5)Cotter Pin
(6)Upper Control Arm Front Seal Grease Fitting
(7)Upper Control Arm Front Bushing
(8)Upper Control Arm Front Seal
(9)Upper Control Arm
(10)Upper Control Arm Pivot Shaft Nuts
(11)Upper Control Arm Rear Seal
(12)Upper Control Arm Rear Bushing
(13)Upper Control Arm Rear Seal Grease Fitting
(14)Upper Control Arm Pivot Shaft Spacer
(15)Shim Pack
(16)Upper Control Arm Frame Bracket
(17)Upper Control Arm Pivot Shaft Bolt
(18)Reinforcement to Frame Washer
(19)Reinforcement to Frame Bolt
(20)Reinforcement
(21)Frame Bracket Washer
(22)Frame bracket Nut
(23)Shim Pack
(24)Upper Control Arm Pivot Shaft Spacer
(25)Upper Control Arm Pivot Shaft
.

  1. Install the suspension and crossmember unit. Raise the unit with the hoist and align the suspension crossmember and frame holes.

  2. Object Number: 175300  Size: SH
  3. Install the suspension crossmember to frame rail bolts (10), the washers (9), and the nuts (8).
  4. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

    Important: The upper control arm to frame bracket bolts must be tightened first.

    The crossmember must be in contact with the frame lower flange.

  5. Install the upper control arm to frame bracket bolts (6), the washers (5), and the nuts (13).
  6. Tighten

        • For commercial models, tighten the bolts to 87 N·m (64 lb ft).
        • For motorhome models, tighten the bolts to 135 N·m (100 lb ft).
  7. Install the crossmember to frame bolts (1) through the reinforcement.
  8. Install the washers (2) and the nuts as used.
  9. Tighten

        • For commercial models, tighten the bolts to 87 N·m (64 lb ft).
        • For motorhome models, tighten the bolts to 135 N·m (100 lb ft).
  10. Install the engine mount support bracket to suspension crossmember bolts. Remove the engine support and lower the hoist. Refer to Engine Mount Replacement or Engine Mount Replacement or Engine Mount Replacement or Engine Mount Replacement in Engine Mechanical.
  11. Install the brake line clip to the crossmember.

  12. Object Number: 175279  Size: SH
  13. Install the shock absorber to the lower control arm.
  14. Install the washers, the nuts, and the bolts.
  15. Tighten
    Tighten the nut to 102 N·m (75 lb ft).


    Object Number: 175282  Size: SH
  16. Install the stabilizer shaft (5) to the lower control arm.
  17. Install the bracket (1), the bolts (2), and the nuts (3).
  18. Tighten
    Tighten the nut to 33 N·m (24 lb ft).

  19. Connect the tie rod ends to the steering knuckle. Refer to Tie Rod Replacement in Steering Linkage.
  20. Connect the brake hose to the caliper.
  21. 13.1. For commercial vehicles, refer to Front Brake Hose Replacement in Hydraulic Brakes.
    13.2. For motorhome vehicles, refer to Front Brake Hose Replacement in Hydraulic Brakes.
  22. Install the brake hose clips to the upper control arms.
  23. Bleed the brake system. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
  24. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  25. Lower the vehicle.
  26. Connect the negative battery cable.
  27. Check the front wheel alignment. Refer to Wheel Alignment Specifications in Wheel Alignment.