Axle Lubricant Change 8.6. 9.5, 10.5 Inch Axle

1. Raise the vehicle on a hoist.
2. Remove the rear axle fill plug.



3. Remove the rear axle housing cover and the gasket (8.6 inch axle only).

3.1.	Drain the oil into a suitable container.

3.2.	Remove any gasket material from the rear axle housing and/or the rear axle housing cover.

1. Install the new rear axle housing gasket and the rear axle housing cover (8.6 inch axle).

Notice: Refer to Fastener Notice in the Preface section.

2. Install the rear axle housing cover bolts.

Tighten
Tighten the rear axle housing cover bolts in a crosswise pattern to 40 N·m (30 lb ft).

3. Fill the rear axle with lubricant level to the filler plug hole. Refer to Fluid and Lubricant Recommendations in Maintenance and Lubrication.
4. Install the rear axle fill plug.

Tighten
Tighten the rear axle fill plug to 40 N·m (30 lb ft).

5. Lower the vehicle.

Axle Lubricant Change 11 Inch Axle

1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.



2. Remove the fill plug.
3. Remove the rear axle housing cover bolts.
4. Remove the rear axle housing cover.

Drain the lubricant into a suitable container.

5. Remove the sealant from the rear axle housing and the rear axle housing cover.

1. Apply an approximately 3.18-6.35 mm (1/8-1/4 in) high and 3.18-6.35 mm (1/8-1/4 in) wide bead of sealant (GM P/N 12346240 or equivalent) to the rear axle housing cover.

The sealant is to be applied in the middle of the rear axle housing cover flange and on the inside of all bolt hole openings as shown.




2. Install the rear axle housing cover.

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.

3. Install the rear axle housing cover bolts.

Tighten
Tighten the rear axle housing cover bolts to 47 N·m (35 lb ft).

Important: Allow the sealant to cure for 1 hour before filling the axle with axle lubricant.

4. Fill the rear axle with axle lubricant. Use the proper fluid. Refer to Approximate Fluid Capacities and Fluid and Lubricant Recommendations in Maintenance and Lubrication.
5. Install rear axle fill plug.

Tighten
Tighten the rear axle fill plug to 33 N·m (24 lb ft).

6. Lower the vehicle.