GM Service Manual Online
For 1990-2009 cars only

Differential Overhaul 8.6, 9.5LD inche Axles

Disassembly Procedure

  1. Remove the differential ring gear. Refer to Drive Pinion and Ring Gear Replacement
  2. Remove the differential side bearings. Refer to Differential Side Bearings Replacement.

  3. Object Number: 2152359  Size: SH
  4. Remove and discard the differential pinion gear shaft lock bolt (2). Replace with NEW only.
  5. Remove the differential pinion gear shaft (1).
  6. Note: Mark the top and bottom differential pinion gears and thrust washers, if reusing.

  7. Roll the differential pinion gears (7) and the thrust washers (6) out of the differential case 2).
  8. Note: Mark the left and right side differential side gears and the thrust washers, if reusing.

  9. Remove the differential side gears (5) and the thrust washers (4).

Assembly Procedure

  1. Lubricate the pinion and side gears using the proper axle lubricant. Refer to Fluid and Lubricant Recommendations.
  2. Install the differential side gear thrust washers (4) to the differential side gears (5).

  3. Object Number: 2152359  Size: SH

    Note: If the same differential side gears and the thrust washers are being used, install the gears and the thrust washers to their original locations.

  4. Install the differential side gears (5) and thrust washers (4) into the differential case (2).
  5. Position one pinion gear (7) between the differential side gears (5).
  6. Position the second pinion gear (7)  between the differential side gears (5).
  7. Rotate the differential side gears (5)  until the pinion gears (7)  are directly opposite the opening in the differential case (2).
  8. Rotate the pinion gears (7)  toward the differential opening.
  9. Install the thrust washers (6) on the pinion gears (5).
  10. Rotate the pinion gears until they are aligned with the holes in the differential case (2) for the pinion shaft (1).
  11. Install the pinion shaft (1).
  12. Caution: Refer to Fastener Caution in the Preface section.

  13. Install the NEW differential pinion gear shaft locking bolt and tighten to.
  14. • For the 8.6 inch axle, tighten the pinion bolt to 36 N·m (27 lb ft).
    • For the 9.5 inch axle, tighten the pinion bolt to 50 N·m (37 lb ft).
  15. Install the differential ring gear to the differential case. Refer to Drive Pinion and Ring Gear Replacement.
  16. Install the differential side bearings. Refer to Differential Side Bearings Replacement.

Differential Overhaul 10.5 Inch Axle

Disassemble Procedure

  1. Remove the differential side bearings. Refer to Differential Side Bearings Replacement.
  2. Remove the differential ring gear. Refer to Drive Pinion and Ring Gear Replacement.

  3. Object Number: 2153858  Size: SH
  4. Separate the differential case (1).

  5. Object Number: 2153694  Size: SH

    Note: If the differential pinion gears, the differential side and the thrust washers are going to be reused, mark the components so they can be re-installed in their original location in the differential case.

  6. Remove the pinion gears (2), thrust washers (1) and the differential spider (3) from the differential case (6).
  7. Remove the differential side gears (4) and the thrust washers (5) from the differential case (5).

Assemble Procedure

  1. Apply a small amount of the proper gear lubricant to the differential side gears and the differential pinion gears. Refer to Fluid and Lubricant Recommendations.

  2. Object Number: 2153694  Size: SH

    Note: If reusing the differential side and pinion gears, install them in the original position.

  3. Install the thrust washers (5) differential side gears (4) into the differential case (6).
  4. Install the differential pinion gears (2), thrust washer (1) on the differential spider (3).
  5. Note: When installing the differential spider and gears assembly, rotate the differential side gears until the

  6. Position the differential thrust washers (1), pinion gears (2) and the spider (3) in the differential case (5).

  7. Object Number: 739964  Size: SH
  8. Align the arrows on the differential case halves before

  9. Object Number: 2153858  Size: SH
  10. Position the differential side gear (3) and the thrust washer (3) on the differential pinion gears (4).
  11. Install the differential case half (1).
  12. Install the differential ring gear. Refer to Drive Pinion and Ring Gear Replacement.
  13. Install the differential side bearings. Refer to Differential Side Bearings Replacement.

Differential Overhaul 11.5 Inch Axle

Disassemble Procedure

  1. Remove the differential case side bearings. Refer to Differential Side Bearings Replacement.
  2. Remove the differential ring gear from the differential case. Refer to Drive Pinion Bearings Replacement.

  3. Object Number: 850793  Size: SH
  4. Locate the end of the pinion shaft with the pilot hole.

  5. Object Number: 911230  Size: SH
  6. Using a brass drift and a hammer, remove the pinion shaft from the differential case.

  7. Object Number: 911232  Size: SH
  8. Remove and discard the retaining ring from the pinion shaft. Replace with NEW only.

  9. Object Number: 911236  Size: SH

    Note: Mark the differential pinion gears top and bottom

  10. Remove the differential pinion gears and the thrust washers by rolling the differential pinion gears out through the differential case opening.
  11. Note: Mark the differential side gears left and right.

  12. Remove the differential side gears and the thrust washers.

Assemble Procedure


    Object Number: 911232  Size: SH

    Note: Ensure that the retaining ring is properly seated groove.

  1. Install the NEW retaining ring on the differential pinion shaft.
  2. Using the proper axle lubricant, lubricate the pinion and side gears. Refer to Fluid and Lubricant Recommendations.
  3. Note: If the same differential side gears and the thrust washers are being used, install the gears and the thrust washers to their original locations.

  4. Install the differential side gear thrust washers to the differential side gears.
  5. Install the differential side gears and thrust washers in the differential case.

  6. Object Number: 911236  Size: SH

    Note: If the same differential side gears and the thrust washers are being used, install the gears and the thrust washers to their original locations.

  7. Install the thrust washers to the pinion gears.
  8. Position one of the pinion gears with the thrust washer between the differential side gears.
  9. Install the second pinion gear with the thrust washer between the differential side gears directly opposite of the first gear.
  10. Rotate the differential side gears until the pinion gears and the thrust washers are directly opposite the opening in the differential case.

  11. Object Number: 911245  Size: SH

    Note: When installing the differential pinion shaft, slide differential pinion until the retaining ring is against the differential case.

  12. Using a brass drift and a hammer, install the differential pinion shaft.
  13. Install the differential ring gear on the differential case. Refer to Drive Pinion Bearings Replacement.

  14. Object Number: 651740  Size: SH
  15. Install the differential side bearings. Refer to Differential Side Bearings Replacement.