GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 8001 Dial Indicator
    • J 42143 Side Bearing Preload Clamp
    • J 42149 Side Bearing Preload Clamp Plate
    • J 42178 Differential Side and Pinion Alignment Kit

The differential carrier side bearing preload is maintained by the thickness of the differential side bearing adjuster rings (snap rings). It is recommended that you have a selection of adjuster rings nearby when setting the side bearing preload.

  1. Use the cover bolts to install the J 42149 onto the rear axle housing cover surfaces.
  2. Tighten
    Tighten the cover bolts until fully seated. Do NOT strip the cover bolts.


    Object Number: 218734  Size: SH
  3. Install the J 42149 between the side bearing race and the J 42143 .
  4. Install the J 8001 onto the J 42143 with the indicator button resting on the ring gear surface.
  5. Install the differential carrier with the bearing races into the rear axle housing.

  6. Object Number: 218736  Size: SH
  7. Use heavy duty snap ring pliers to install the left adjuster ring.
  8. Install the right snap rings of various thickness until you are able to read no movement of the differential carrier on the J 8001 .
  9. Add an additional 0.125 mm (0.005 in) to each side in the adjuster ring thickness once the zero carrier movement is achieved. Note the Total Preload on Bearings is 0.25 mm (0.010 in). The side bearing preload is now correctly established.
  10. Important: If it is necessary to vary the adjuster ring thickness, once the side bearing preload has been established, then always maintain the same total thickness between the two snap rings to maintain the preload. For instance, if it was required that 0.002 inches be removed from the left side adjuster ring thickness to correctly establish the backlash and to correct the contact pattern, then 0.002 inches must be added to the right side adjuster ring thickness in order to maintain the side bearing preload.

  11. The rotating torque of the carrier should be between 5 - 6 (+/- 0.5) inch pounds with lubricated bearings. Use the following tools to verify the rotating torque of the differential carrier as installed with the correct adjuster rings:
  12. • Use the J 42178 .
    • Use the appropriate adapters.
    • Use an inch-pound torque wrench.