Chevrolet Silverado / GMC Sierra. Service manual — part 1490

Fig. 282: View Of Locking Differential Clutch Disc Assembly (9.5 Inch Axle)
Courtesy of GENERAL MOTORS CORP.

1. Apply axle lubricant, GM P/N 12378261 (Canadian P/N 10953455) or equivalent meeting

GM Specification 9986115, to the surface of each disc.

2. Assemble the right side or bell-end side clutch disc assembly as follows:

1. Install the 1st non-carbon eared disc (3) to the side gear (1).

2. Install the 1st splined disc (4).

3. Install the 2nd non-carbon eared disc (5).

4. Install the 2nd splined disc (6).

5. Install the 3rd non-carbon eared disc (7).

6. Install the guide clips (2) to the clutch discs (2-7).

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Apply chassis grease, GM P/N 12377985 (Canadian P/N 88901242) or equivalent, to
the guide clips in order to hold the clips in place on the disc ears.

LOCKING DIFFERENTIAL ADJUSTMENT (8.6 INCH AXLE)

Tools Required

J 7872 Magnetic Base Dial Indicator. See Special Tools.

J 8001 Dial Indicator Set

Adjustment of the Differential

When adjusting the differential, note the following:

Build up the clutch disc assemblies properly.

Proper clearance between parts is critical to the operation of the unit.

Adjust the backlash and thrust block clearance in the following order:

1. The left side gear backlash

2. The right side gear backlash

3. The thrust block clearance

Left Side Gear Backlash Adjustment

IMPORTANT: If it is necessary to replace the left side locking differential side

gear cam unit and clutch disc assembly, the right side locking
differential side gear and clutch disc assembly, or the thrust
block, the entire differential must be adjusted. The differential is
adjusted using selective thickness thrust washers between the
clutch disc assemblies and the case and/or different selective
thickness thrust blocks.

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 283: View Of Left Side Gear Thrust Washer
Courtesy of GENERAL MOTORS CORP.

1. Install the new locking differential clutch disc thrust washer into the left side or flange-end

of the differential case.

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 284: View Of Left Side Gear Cam Unit & Clutch Disc Assembly
Courtesy of GENERAL MOTORS CORP.

2. Install the locking differential side gear cam unit and clutch disc assembly into the left side

or flange-end of the differential case.

3. Install the differential pinion gears with the differential pinion gear thrust washers into the

differential case.

Align the openings of the differential pinion gears and the differential pinion gear thrust
washer to the pinion shaft opening in the differential case.

4. Install the pinion shaft. It may be necessary to press down on the locking differential side

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado