GM Service Manual Online
For 1990-2009 cars only

Differential Replacement 8.6, 9.5 Inch Axle

Tools Required

J 24429 Side Bearing Backlash Spanner

Removal Procedure

Important: Group and mark the shims together as originally removed. If you remove or replace the ring and pinion gearset, perform the bearing preload, backlash, and gear tooth contact pattern check in order to ensure proper contact of the gears. If you reinstall or replace the differential carrier without replacing any other component (i.e. pinion and ring gear set, bearings. etc.) then you may reinstall the carrier with the original shims in their original locations. Always perform a gear tooth contact pattern check, even when you remove only the carrier.

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the tires and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  3. Remove the brake drums. Refer to Brake Drum Replacement in Drum Brakes.
  4. Remove the rear axle housing cover and the gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  5. Remove the axle shafts. Refer to Rear Axle Shaft Replacement .

  6. Object Number: 667492  Size: SH
  7. Remove the differential bearing adjuster nut lock (9.5 inch axle - right side).

  8. Object Number: 667502  Size: SH
  9. Remove the bearing caps and bolts. Mark the bearing caps left and right.
  10. Caution: To prevent personal injury and/or component damage, support the differential case when removing the case from the axle housing. If the case is not supported, the differential case could fall and cause personal injury or damage to the differential case.

    Notice: When removing the differential case from the axle housing, do not damage the cover gasket surface. If the cover gasket surface is damaged, lubricant may leak from the axle and cause premature failure of the axle assembly.


    Object Number: 9730  Size: SH
  11. Remove the differential by prying the differential from the axle housing at the differential window (8.6 inch axle).
  12. Loosen the differential bearing adjuster nut using the J 24429 (9.5 inch axle).
  13. Remove the differential (9.5 inch axle).
  14. Remove the bearing cups, the shims, and the spacers as necessary.
  15. Mark the cups and shims left and right and in the proper order as necessary. Place the cups and the shims with the bearing caps.

  16. Remove the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  17. Remove the ring gear, if necessary. Refer to Drive Pinion and Ring Gear Replacement .

Installation Procedure

  1. Install the ring gear, if necessary. Refer to Drive Pinion and Ring Gear Replacement .
  2. Install the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  3. Lubricate the differential side bearings with axle lubricant. Use the proper fluid. Refer to Fluid and Lubricant Recommendations in Maintenance and Lubrication.

  4. Object Number: 667660  Size: SH
  5. Place the case, with the bearing cups installed, into the axle housing.
  6. Support the case in order to keep the case from falling out of the axle housing.


    Object Number: 667502  Size: SH
  7. Install the bearing caps and the bolts.
  8. Do not torque the bearing cap bolts at this time.

  9. Adjust the differential side bearing preload. Refer to Differential Carrier Bearing Preload Adjustment .
  10. Adjust the backlash. Refer to Backlash Adjustment .
  11. Perform a gear tooth contact pattern check. Refer to Gear Tooth Contact Pattern Inspection .
  12. Install the bearing cap bolts.
  13. Tighten
    Tighten the bearing cap bolts to 85 N·m (63 lb ft).

  14. Install the differential bearing adjuster nut lock.
  15. Install the differential bearing adjuster nut lock bolt.
  16. Tighten
    Tighten the differential bearing adjuster lock nut bolt to 26 N·m (19 lb ft).

  17. Install the axle shafts. Refer to Rear Axle Shaft Replacement .
  18. Install the rear axle housing cover and a new gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  19. Install the brake drums. Refer to Brake Drum Replacement in Drum Brakes.
  20. Install the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  21. Fill the axle with lubricant. Use the proper fluid. Refer to Approximate Fluid Capacities and Fluid and Lubricant Recommendations in Maintenance and Lubrication.
  22. Lower the vehicle.

Differential Replacement 11 Inch Axle

Tools Required

    • J 26900-13 Magnetic Indicator Base
    • J 24385-C Axle Housing Spreader
    • J 8001 Dial Indicator

Removal Procedure

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the axle shafts. Refer to Rear Axle Shaft and/or Gasket Replacement .
  3. Remove rear axle housing cover. Refer to Rear Axle Housing Cover and Gasket Replacement .
  4. Remove the bearing cap bolts.
  5. Important: Corresponding letters are stamped on the bearing caps and axle housing. The bearing caps must be reassembled in the same position as removed.

  6. Remove the bearing caps.
  7. Install the J 8001 to the J 26900-13 .

  8. Object Number: 756302  Size: SH

    Caution: To prevent personal injury and/or component damage, support the differential case when removing the case from the axle housing. If the case is not supported, the differential case could fall and cause personal injury or damage to the differential case.

  9. Install the J 24385-C (2), the J 26900-13 , and the J 8001 (1) to the differential housing as shown.
  10. Preset the gage to a minimum of 5 mm (0.200 in). Rotate the indicator housing to on the dial to align the indicator needle and the indicator housing to zero.
  11. Notice: Do not spread the axle housing more than 0.38 mm (0.015 inch). Overspreading the housing may result in component damage.

  12. Spread the housing while examining the J 8001 .

  13. Object Number: 168049  Size: SH
  14. Remove the case from the housing using 2 pry bars.
  15. Remove the J 24385-C , the J 26900-13 , and the J 8001 from the differential housing.
  16. Important: Mark the differential side bearing preload shims left or right.

  17. Remove the differential side bearing preload shims.
  18. Remove the ring gear. Refer to Drive Pinion and Ring Gear Replacement .
  19. Remove the differential side bearings. Refer to Differential Side Bearings Replacement .

Installation Procedure

  1. Determine the total shim pack size for the differential case assembly. Refer to Determining Total Shim Pack Size .
  2. Install the axle shafts. Refer to Rear Axle Shaft and/or Gasket Replacement .
  3. Install the rear axle housing cover. Refer to Rear Axle Housing Cover and Gasket Replacement .
  4. Fill the axle with lubricant. Use the proper fluid. Refer to Lubricant Change .
  5. Lower the vehicle.

Differential Replacement 10.5 Inch Axle

Tools Required

J 24429 Side Bearing Backlash Spanner

Removal Procedure

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the axle shafts. Refer to Rear Axle Shaft and/or Gasket Replacement .
  3. Remove the rear axle housing cover and the gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  4. Remove the differential bearing adjuster nut retainers.
  5. Remove the bearing caps and bolts. Mark the bearing caps left and right.
  6. Caution: To prevent personal injury and/or component damage, support the differential case when removing the case from the axle housing. If the case is not supported, the differential case could fall and cause personal injury or damage to the differential case.

    Notice: When removing the differential case from the axle housing, do not damage the cover gasket surface. If the cover gasket surface is damaged, lubricant may leak from the axle and cause premature failure of the axle assembly.

  7. Loosen the adjusters using the J 24429 .
  8. Remove the differential.
  9. Remove the bearing cups.
  10. Mark the cups left and right. Place the cups with the bearing caps.

  11. Remove the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  12. Remove the ring gear, if necessary. Refer to Drive Pinion and Ring Gear Replacement .

Installation Procedure

  1. Install the ring gear, if necessary. Refer to Drive Pinion and Ring Gear Replacement .
  2. Install the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  3. Lubricate the differential side bearings with axle lubricant. Use the proper fluid. Refer to Fluid and Lubricant Recommendations in Maintenance and Lubrication.
  4. Place the case, with the bearing cups installed, into the axle housing.
  5. Support the case in order to keep the case from falling out of the axle housing.

  6. Install the bearing caps and the bolts.
  7. Do not torque the bearing cap bolts at this time.

  8. Turn the adjusters evenly on each side using the J 24429 until snug against the differential.
  9. Adjust the differential side bearing preload. Refer to Differential Carrier Bearing Preload Adjustment .
  10. Adjust the backlash. Refer to Backlash Adjustment .
  11. Perform a gear tooth contact pattern check. Refer to Gear Tooth Contact Pattern Inspection .
  12. Notice: Refer to Fastener Notice in the Preface section.

  13. Tighten the bearing cap bolts.
  14. Tighten
    Tighten the bearing cap bolts to 185 N·m (136 lb ft).

  15. Install the differential bearing adjuster nut locks.
  16. Install the differential bearing adjuster nut lock bolts.
  17. Tighten
    Tighten the differential bearing adjuster lock nut bolts to 27 N·m (20 lb ft).

  18. Install the axle shafts and new gaskets. Refer to Rear Axle Shaft and/or Gasket Replacement .
  19. Install the rear axle housing cover and a new gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  20. Fill the axle with lubricant. Use the proper fluid. Refer to Approximate Fluid Capacities and Fluid and Lubricant Recommendations in Maintenance and Lubrication.
  21. Lower the vehicle.