GM Service Manual Online
For 1990-2009 cars only
  1. Raise the vehicle. Support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Place a drain pan or suitable container under the rear axle housing.
  3. Remove the rear axle housing oil level/filler plug from the rear axle housing.
  4. Remove the rear axle housing drain plug from the rear axle housing and drain the rear axle housing.
  5. 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.

  6. After the rear axle housing has completely drained, install the rear axle housing drain plug with a new gasket into the rear axle housing.
  7. Tighten
    Tighten the rear axle housing drain plug to 39 N·m (29 lb ft).

  8. Refill the rear axle housing with approximately 0.5 liters (1.0 pts) of 80W-90 GL5 lubricant GM P/N 12345977 (Canadian P/N 10953482), or equivalent. The oil level should be even with the bottom of the rear axle housing oil level/filler plug hole.
  9. Install the rear axle housing oil level/filler plug with a new gasket into the rear axle housing.
  10. Tighten
    Tighten the rear axle housing oil level/filler plug to 39 N·m (29 lb ft).

  11. Remove the drain pan from under the rear axle housing.
  12. Lower the vehicle.