Chevrolet Silverado / GMC Sierra. Service manual — part 1376

Fig. 197: Installing Inner Pinion Bearing Cup Into Differential Carrier Case J
36598-4 & J 36598-15 (8.25/9.25 Inch Axles)
Courtesy of GENERAL MOTORS CORP.

11. Place the J 36598-3, 8.25 inch axle, or the J 36598-4, 9.25 inch axle (2), over the inner

pinion bearing cup.

12. Extend the forcing screw of the J 36598 (1) through the J 36598-15 and thread it into the J

36598-3 or the J 36598-4 (2) until fully seated.

13. Rotate the J 36598-3 or the J 36598-4 several times in order to ensure the inner pinion

bearing cup is evenly seated and not mis-aligned in the bore.

14. Install the inner pinion bearing cup into the differential carrier case half by holding the

2008 Chevrolet Silverado 1500

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

forcing screw of the J 36598 and turning the handle clockwise.

Inspect the position of the inner pinion bearing cup as it is being drawn into the inner pinion
bearing cup bore to ensure the bearing cup is being installed evenly. If the pinion bearing
cup is not being installed evenly, loosen the J 36598 and remove the inner pinion bearing
cup. See Special Tools. Reposition the inner pinion bearing cup over the inner pinion
bearing cup bore and re-install.

15. Remove the J 36598-3 or the J 36598-4 and the J 36598-15.

16. Remove the differential carrier case.

17. Remove the J 36598 from the vise.

18. Determine the selective shim thickness for the pinion. Refer to Pinion Depth Adjustment.

PINION DEPTH ADJUSTMENT

Tools Required

J 36601 Pinion Shim Selector. See Special Tools.

J 29763 Static Timing Gage. See Special Tools.

Adjustment

1. Install the pinion bearing cups into the differential carrier assembly. Refer to Front

Differential Drive Pinion Gear Bearing Cup Installation (9.25 Inch Axle w/J 45754)
or Front Differential Drive Pinion Gear Bearing Cup Installation (8.25 Inch Axle w/J
45858) or Front Differential Drive Pinion Gear Bearing Cup Installation (8.25/9.25
Inch Axles w/J 36598).

2. Before assembly, lubricate the pinion bearings with axle lubricant. Use the correct fluid.

Refer to Sealers, Adhesives, and Lubricants.

IMPORTANT: Make sure all of the tools, the pinion bearings, and the pinion

bearing cups are clean before proceeding.

2008 Chevrolet Silverado 1500

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

Fig. 198: Using J 36601-7, J 36601-5, J 21777-8 & J 36601-3 To Adjust Pinion Depth
Courtesy of GENERAL MOTORS CORP.

3. Install the J 36601-4 or the J 36601-3 (4) to the J 36601-7 (1).

4. Install the J 21777-35 for the 8.25 inch axle or the J 21777-8 for the 9.25 inch axle (3) to

the J 36601-7 (1).

5. Install the inner pinion bearing into the differential carrier case half.

IMPORTANT: The J 36601 uses two different measuring arms to measure

the pinion depth. See Special Tools. The J 36601-4 is used to
measure the pinion depth for the 8.25 inch axle and the J
36601-3 is used to measure the pinion depth for the 9.25 inch
axle.

2008 Chevrolet Silverado 1500

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

6. Insert the J 36601-7 (1) with the J 21777-35 or the J 21777-8 (3) through the inner pinion

bearing and the differential carrier case half.

7. Install the outer pinion bearing.

8. While holding the outer pinion bearing in position, install the J 36601-5 (2), the washer, and

the nut to the J 36601-7 (1).

9. While holding the J 36601-7 (1) stationary with a wrench, tighten the nut on the J 36601-7

(1).

Tighten: Tighten the nut until all of the end play is removed from the J 36601 . See
Special Tools.

10. Rotate the assembly several times in both directions in order to seat the pinion bearings.

11. While holding the J 36601-4 or the J 36601-3 (4) stationary, measure the rotating torque of

the J 36601 using an inch-pound torque wrench. See Special Tools.

Specification: The rotating torque of the J 36601 should be between 1. See Special
Tools.1-2.3 N.m (10-20 lb in).

12. If the torque is less than 1.0 N.m (10 lb in), continue to tighten the nut on the J 36601-7

until a rotating torque of 1.1-2.3 N.m (10-20 lb in) is obtained.

IMPORTANT: Each end of the J 36601-5 is sized specifically for the 8.25

inch or the 9.25 inch outer pinion bearing. Ensure the correct
end is being used when installing the J 36601-5 into the outer
pinion bearing.

NOTE:

Refer to Fastener Notice .

2008 Chevrolet Silverado 1500

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