GM Service Manual Online
For 1990-2009 cars only

Draining Procedure


    Object Number: 1247991  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Clean any dirt from around the differential drain plug.
  3. Remove the drain plug and washer from the differential.
  4. Drain the fluid.

Filling Procedure

    Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1247991  Size: SH
  1. Install the drain plug and washer to the differential and tighten the differential drain plug to 35 N·m (26 lb ft).

  2. Object Number: 1247990  Size: SH
  3. Clean any dirt from around the differential fill plug.
  4. Note: DO NOT add any limited-slip additive (friction modifier). With Dexron LS Gear Oil 75W-90 it is no longer required to add friction modifier. If friction modifier is added, it will cause the fluid to lose some of the friction reducing properties as well as reducing seal life.

  5. Remove the fill plug and washer from the differential.
  6. Fill the differential with fluid. Refer to Lubrication Specifications.
  7. Check the fluid level to ensure it is even with the bottom of the fill plug hole to no lower than 6 mm (0.25 in) below the opening.
  8. Install the fill plug and washer to the differential and tighten the differential fill plug to 35 N·m (26 lb ft).
  9. Lower the vehicle.