GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 25588 Side Bearing Shim Installer

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Place a drain pan under rear axle cover.
  3. Remove the rear axle cover and the gasket. Drain the rear axle fluid. Refer to Rear Axle Housing Cover and Gasket Replacement .
  4. Remove rear axle shafts. Refer to Rear Axle Shaft Replacement .

  5. Object Number: 164023  Size: SH
  6. Remove the differential carrier bearing cap bolts (2, 3).
  7. Remove the differential carrier bearing caps (4) by moving the bearing caps from side to side.
  8. Do not pry on the bearing cap parting surfaces.


    Object Number: 164239  Size: SH

    Important: Group the shims together with the original installed location labeled. If you remove or replace the ring and pinion gearset, perform the bearing preload, backlash, and tooth contact pattern test in order to ensure proper contact of the gears. If you reinstall or replace the differential carrier without replacing any other component, e.g. pinion and ring gear set, bearings, etc., then you may reinstall the carrier with the original shims in the original locations. Always perform a gear tooth contact pattern check, even if only removing the carrier.

  9. Remove the differential carrier (1) and the shims from the rear axle housing (2).

Installation Procedure


    Object Number: 375040  Size: SH
  1. Install the differential carrier and the shims (1) into the housing (2), ensuring that the shims are in the original location, using the J 25588 and a deadblow hammer.

  2. Object Number: 164023  Size: SH

    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.

  3. Install the differential bearing caps (4) and cap bolts (2, 3).
  4. Tighten
    Tighten the differential bearing cap bolts to 75 N·m (55 lb ft).

  5. Perform a backlash adjustment. Refer to Backlash Adjustment .
  6. Perform a gear tooth contact pattern check. Refer to Gear Tooth Contact Pattern Inspection .
  7. Install the rear axle shafts. Refer to Rear Axle Shaft Replacement .
  8. Install the rear axle cover and the gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  9. Lower the vehicle.
  10. Road test the vehicle in order to ensure proper differential operation.