Hummer H3. Manual — part 1028

See Special Tools.

5. Install the J 7872-3 (4) to the J 8001-3 (3). See Special Tools.

6. Place the contact pad of the J 7872-3 (4) onto one of the teeth of the pinion gear

closest to the locking differential side gear.

Preload the dial of the J 8001-3 approximately 3/4 of a turn clockwise. See Special
Tools.

7. Tighten the lock nut of the J 7872-2 (2) finger tight.

8. Turn the dial of the J 8001-3 until the needle and the dial face indicate ZERO. See

Special Tools.

9. Pull the pinion gear firmly into the differential case seat.

10. Rotate the pinion gear back and forth.

11. Measure the backlash.

Specification: The backlash between the locking differential side gear and the pinion
gears should be 0.051-0.076 mm (0.002-0.003 in).

10. If the backlash is too large, disassemble the differential, install the next larger size side gear

thrust washer, re-assemble the differential and recheck the backlash.

11. If the backlash is too small, disassemble the differential, install next smaller size side gear

thrust washer, re-assemble the differential and recheck the backlash.

Differential side gear thrust washers are available in the following sizes:

Washer Sizes:

19.05 mm (0.750 in)

20.32 mm (0.800 in)

21.59 mm (0.850 in)

22.86 mm (0.900 in)

24.13 mm (0.950 in)

25.40 mm (1.000 in)

26.67 mm (1.050 in)

27.94 mm (1.100 in)

29.21 mm (1.150 in)

30.48 mm (1.200 in)

2007 Hummer H3

2007 Driveline/Axle Rear Drive Axle - H3

31.75 mm (1.250 in)

LOCKING DIFFERENTIAL ASSEMBLE

1. Measure the backlash of the pinion gears to differential side gear and locking differential

side gear. Refer to Locking Differential Adjustment.

Fig. 156: View Of Locking Differential Side Gear & Thrust Washer
Courtesy of GENERAL MOTORS CORP.

IMPORTANT:

If the same differential side gears and the thrust washers are
being used, install the differential side gears and the thrust
washers in their original locations.

The locking differential side gear and the differential side
gear are not interchangeable. The side gears must be
installed in the correct location in order for the locking
differential to function properly.

2007 Hummer H3

2007 Driveline/Axle Rear Drive Axle - H3

2. Install the differential side gear thrust washer to the locking differential side gear.

3. Install the locking differential side gear and thrust washer into the ring gear side of the

differential case.

Fig. 157: Differential Side Gears & Thrust Washers
Courtesy of GENERAL MOTORS CORP.

4. Install the differential side gear thrust washer to the differential side gear.

5. Install the differential side gear and thrust washer into the bell side of the differential case.

2007 Hummer H3

2007 Driveline/Axle Rear Drive Axle - H3

Fig. 158: Identifying Differential Pinion Gears & Thrust Washers
Courtesy of GENERAL MOTORS CORP.

6. Install the differential pinion gears and thrust washers by doing the following:

1. Position both pinion gears and thrust washers between the differential side gears.

Place the pinion gears and thrust washers 180 degrees across from each other.

2. Rotate the differential side gears until both pinion gears and thrust washers are directly

opposite the opening in the differential case.

Line up the pinion shaft opening in each of the pinion gears with the pinion shaft
opening in the differential case.

2007 Hummer H3

2007 Driveline/Axle Rear Drive Axle - H3