GM Service Manual Online
For 1990-2009 cars only

Differential Replacement 8.6 Inch, 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 gear set, 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 calipers. Refer to Rear Brake Caliper Replacement in Disc Brakes.
  4. Remove the brake rotors. Refer to Rear Brake Rotor Replacement in Disc Brakes.
  5. Remove the rear axle housing cover and the gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  6. Remove the axle shafts. Refer to Rear Axle Shaft Replacement .

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

  9. Object Number: 667502  Size: SH
  10. Remove the bearing caps and bolts. Mark the bearing caps left and right.
  11. 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
  12. Remove the differential by prying the differential from the axle housing at the differential window (8.6 inch axle).
  13. Loosen the differential bearing adjuster nut using the J 24429 (9.5 inch axle).
  14. Remove the differential (9.5 inch axle).
  15. Remove the bearing cups, the shims, and the spacers as necessary.
  16. 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.

  17. Remove the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  18. 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. Tighten the bearing cap bolts.
  13. Tighten

        • For the 8.6 inch axle, tighten the bearing cap bolts to 75 N·m (55 lb ft)
        • For the 9.5 inch axle, tighten the bearing cap bolts to 85 N·m (63 lb ft)
  14. Install the axle shafts. Refer to Rear Axle Shaft Replacement .
  15. Install the rear axle housing cover and a new gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  16. Install the brake rotors. Refer to Rear Brake Rotor Replacement in Disc Brakes.
  17. Install the brake calipers. Refer to Rear Brake Caliper Replacement in Disc Brakes.
  18. Install the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  19. Fill the axle with lubricant. Use the proper fluid. Refer to Approximate Fluid Capacities and Fluid and Lubricant Recommendations in Maintenance and Lubrication.
  20. Lower the vehicle.

Differential Replacement 10.5 Inch, 11.5 Inch Axle

Tools Required

J 24429 Side Bearing Backlash Spanner

Removal Procedure

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle .
  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. Object Number: 667492  Size: SH
  5. Remove the differential bearing adjuster nut retainers.

  6. Object Number: 667502  Size: SH
  7. Remove the bearing caps and bolts. Mark the bearing caps left and right.
  8. 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.

  9. Loosen the adjusters using the J 24429 .

  10. Object Number: 667660  Size: SH
  11. Remove the differential.
  12. Remove the bearing cups.
  13. Mark the cups left and right. Place the cups with the bearing caps.

  14. Remove the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  15. 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 .

  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.


    Object Number: 694535  Size: SH
  9. Turn the adjusters evenly on each side using the J 24429 until snug against the differential.
  10. Adjust the differential side bearing preload. Refer to Differential Carrier Bearing Preload Adjustment .
  11. Adjust the backlash. Refer to Backlash Adjustment .
  12. Perform a gear tooth contact pattern check. Refer to Gear Tooth Contact Pattern Inspection .
  13. 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.

  14. Tighten the bearing cap bolts.
  15. Tighten

        • Tighten the bearing cap bolts to 185 N·m (136 lb ft) (10.5 inch axle).
        • Tighten the bearing cap bolts to 207 N·m (153 lb ft) (11.5 inch axle).
  16. Install the axle shafts and new gaskets. Refer to Rear Axle Shaft and/or Gasket Replacement .
  17. Install the rear axle housing cover and a new gasket. Refer to Rear Axle Housing Cover and Gasket Replacement .
  18. Fill the axle with lubricant. Use the proper fluid. Refer to Approximate Fluid Capacities and Fluid and Lubricant Recommendations .
  19. Lower the vehicle.

Differential Replacement 9.75 Inch Axle

Tools Required

    • J 24385-C Axle Housing Spreader
    • J 25025 Guide Pins
    • J 34178 Spreader Gage Adapter
    • J 8001 Dial Indicator Set

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 Replacement .
  3. Loosen the bearing cap bolts.
  4. Do not remove the bearing cap bolts at this time.


    Object Number: 815461  Size: SH
  5. Install the J 24385-C onto the axle housing as shown.

  6. Object Number: 815667  Size: SH
  7. Install the J 25025  (2), the J 8001-1 and the J 8001-2  (1), the J 34178  (3), and the J 8001-3 and the J 8001-4  (4) onto the axle housing as shown.
  8. Preload the dial of the J 8001-3 by pushing the J 8001-3 against the edge of the J 24385-C until the needle of the J 8001-3 has moved approximately 3/4 of a turn clockwise.
  9. Rotate the indicator housing to align the indicator needle of the J 8001-3 and the dial indicator face to ZERO.
  10. Notice: Do not spread the axle housing more than 0.38 mm (0.015 inch). Overspreading the housing may result in component damage.

  11. Spread the axle housing by turning the clevis screw of the J 24385-C clockwise while observing theJ 8001 .
  12. Spread the housing just enough to remove the differential assembly.

  13. Remove the J 25025-B , the J 8001-1 , the J 8001-2 , the J 34178 , the J 8001-3 and the J 8001-4 from the axle housing.
  14. Remove the bearing cap bolts.
  15. 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.

    Important: Corresponding letters are stamped on the bearing caps and axle housing. The bearing caps must be reassembled in the same position as removed.

  16. Remove the bearing caps.
  17. Remove the differential assembly.
  18. Remove the J 24385-C .
  19. Remove the ring gear. Refer to Drive Pinion and Ring Gear Replacement .
  20. Remove the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .

Installation Procedure

  1. Install the ring gear. Refer to Drive Pinion and Ring Gear Replacement .
  2. Determine the shim thickness and preload for the differential assembly. Refer to Differential Carrier Bearing Preload Adjustment .
  3. Install the differential side bearings, if necessary. Refer to Differential Side Bearings Replacement .
  4. Install the J 24385-C onto the axle housing.

  5. Object Number: 815592  Size: SH
  6. Install the J 25025-B  (4), the J 8001-1 and the J 8001-2  (5, 1), the J 34178  (2), and the J 8001-3 and the J 8001-4  (3) onto the axle housing as shown.
  7. Preload the dial of the J 8001-3 by pushing the J 8001-3 against the edge of the J 24385-C until the needle of the J 8001-3 has moved approximately 3/4 of a turn clockwise.
  8. Rotate the indicator housing to align the indicator needle of the J 8001-3 and the dial indicator face to ZERO.
  9. Notice: Do not spread the axle housing more than 0.38 mm (0.015 inch). Overspreading the housing may result in component damage.

  10. Spread the axle housing by turning the clevis screw of the J 24385-C clockwise while observing theJ 8001 .
  11. Spread the housing just enough to install the differential assembly.

  12. Remove the J 25025-B , the J 8001-1 , the J 8001-2 , the J 34178 , the J 8001-3 and the J 8001-4 from the axle housing.
  13. Install the differential assembly.
  14. Remove the J 24385-C .
  15. Important: Corresponding letters are stamped on the bearing caps and axle housing. The bearing caps must be reassembled in the same position as removed.

  16. Install the bearing caps.
  17. 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.

  18. Install the bearing cap bolts.
  19. Tighten
    Tighten the bearing cap bolts to 108 N·m (80 lb ft).

  20. Install the axle shafts. Refer to Rear Axle Shaft Replacement .
  21. Fill the axle with lubricant. Use the proper fluid. Refer to Lubricant Change .
  22. Lower the vehicle.