GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 7079-2 Universal Driver Handle - Non-Threaded
    • J 44385 Differential Bearing Race and Seal Installer
    • J 44388 Final End Checking Fixture

    Important: Shimming is only required with the replacement of one or more of the following:

       • Transmission case halves
       • Differential assembly
       • Differential bearing


    Object Number: 678913  Size: SH

    Important: Remove all of the old shims before performing the Shimming Procedures.

  1. Make sure the bearings are fully seated in the case.

  2. Object Number: 678917  Size: SH
  3. Position the transaxle on a bench so that the bearings are resting on a flat surface.
  4. Using a rubber mallet, tap lightly on the case mating surface to ensure the bearings are fully seated.

  5. Object Number: 678924  Size: SH
  6. Measure the distance of the transaxle case parting surface to the output shaft gear thrust washer surface using the J 44388-1.
  7. Place the J 44388-1 on the case parting surface.
  8. Extend the gage rod on the J 44388-1 until it is bottomed on the output shaft gear thrust washer.
  9. Tighten the thumbscrew on the J 44388-1 to retain the gage rod.

  10. Object Number: 678928  Size: SH
  11. Measure and record the length of the gage rod protruding from the gage bar (measurement A).

  12. Object Number: 658871  Size: SH
  13. Make sure the left differential bearing race is fully seated into the transaxle case using the J 7079-2  (1) and the J 44385  (2).

  14. Object Number: 678930  Size: SH
  15. Install the J 44388-2 into the left differential side bearing race. Ensure that the J 44388-2 is fully seated into the left differential side bearing race.

  16. Object Number: 678932  Size: SH
  17. Remove the gage rod from the J 44388-1 (2).
  18. Place the bar of the J 44388-1 (2) onto the gage rod of the J 44388-2 (1).
  19. Tighten the thumbscrew on the J 44388-1 (2) to retain the J 44388-2 (1) gage rod.

  20. Object Number: 678936  Size: SH
  21. Measure the overall height of the J 44388-1 (1) and J 44388-2 (2) (measurement B).

  22. Object Number: 678938  Size: SH
  23. Measure the height of just the J 44388-1 (measurement C).
  24. Subtract the height of the J 44388-1 (measurement C) from the overall height of the J 44388-1 and J 44388-2 (measurement B) and record (measurement D).

  25. Object Number: 678944  Size: SH
  26. Place the differential assembly onto the J 44388-4 to provide a steady measuring surface.

  27. Object Number: 678947  Size: SH
  28. Install the rod back into the J 44388-1 (1).
  29. Place the J 44388-1 (1) across the face of the ring gear.
  30. Center the gage rod of the J 44388-1 (1) over the land for the left differential side bearing shim.
  31. With the gage rod of the J 44388-1 (1) fully seated on the shim land for the left differential side bearing shim, tighten the thumbscrew on the J 44388-1 (1).

  32. Object Number: 678928  Size: SH
  33. Measure and record the length of the gage rod protruding from the J 44388-1 (measurement E).

  34. Object Number: 678952  Size: SH
  35. Remove the vehicle speed sensor (VSS) ring.
  36. Important: Both retaining rings must be removed from the pinion shaft to ensure proper removal of the differential pinion shaft.

  37. Remove and discard both the differential pinion shaft retaining rings and remove the differential pinion shaft.

  38. Object Number: 678959  Size: SH
  39. Insert the J 44388-3 (1) through the center of the differential until it rests firmly on the J 44388-4 (2).

  40. Object Number: 678961  Size: SH
  41. The distance from the top surface of the J 44388-3 (1) to the land of the right differential side bearing shim is measured and recorded (measurement F).
  42. Subtract measurement F from 127 mm (5 in) (measurement G).

  43. Object Number: 678964  Size: SH
  44. To obtain shim size for left differential side shim (1) use the following formula:
  45. Shim (1) = E - A + D - 19.036 mm (0.749 in).

  46. To obtain shim size for right differential side shim (2) use the following formula:
  47. Shim (2) = 94.65 mm (3.726 in) - G - shim (1).