Left Side Gear Backlash Adjustment

1. Install the differential side gear shim.
Fig 1: Installing Differential Side Gear Shim
Courtesy of GENERAL MOTORS CORP.
2. Install the clutch pack assembly.
Fig 2: Installing clutch Pack Assembly
Courtesy of GENERAL MOTORS CORP.
3. Install the differential side gear.
Fig 3: Installing differential Side Gear
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: The washers must be large enough in order to fit over the differential side gear, but not too large to where they will cause an interference with the pinion gear and spider assembly.
4. Assemble a set of washers, a nut, and a bolt long enough in order to hold the side gear in place.
5. Install the bolt and washer assembly through the differential case half.
Fig 4: Installing Bolt & Washer Assembly Through Differential Case Half
Courtesy of GENERAL MOTORS CORP.
6. Install a second set of washers and the nut onto the bolt extending through the differential case half.
7. Install the differential case half into a vise.

   Clamp on the nut on the bottom of the differential case.

8. Install the differential pinion gears, the differential pinion gear thrust washers and the locking differential spider into the case half.
Fig 5: Installing Differential Pinion Gears
Courtesy of GENERAL MOTORS CORP.
9. Loosen the bolt in order to turn the differential side gear.
10. Index the pinion gear so that one tooth is pointing downward, perpendicular to the case half face.
11. Tighten the bolt until the clutch discs are compressed.
12. Install the J 7872  onto the differential case.
13. Loosely clamp the J 8001-3 onto the stem of the J 7872  .
14. Place the contact pad of the J 8001-3 on the tooth that is perpendicular to the differential side gear.
15. Preload the dial of the J 8001-3 approximately one turn clockwise.
16. Tighten the lock nut on the J 7872  finger tight.
17. Turn the dial of the J 8001-3 until the needle and the dial face indicate ZERO.
18. Measure the differential pinion gear to locking differential side gear backlash by performing the following steps:
    • Pull the pinion gear firmly into the seat.
    • Rotate the pinion gear back and forth while reading the dial indicator.

      Do not unseat the locking differential spider. This will make the backlash reading inaccurate.

    • Record the measurement.
Fig 6: Measuring Differential Pinion Gear To Locking Differential Side Gear Backlash
Courtesy of GENERAL MOTORS CORP.
19. Measure the differential pinion gear to locking differential side gear backlash on the other 2 pinion gears following the steps above.

    Specification:  The backlash between the differential pinon gear and locking differential side gear should be between 0.051-0.203 mm (0.002-0.008 in).

20. If the backlash is too large, install a thicker differential side gear shim and recheck the backlash.
21. If the backlash is too small, use a thinner differential side gear shim and recheck the backlash.

Differential side gear shims are available in the following sizes:

Shim Sizes

• 0.254 mm (0.010 in)
• 0.381 mm (0.015 in)
• 0.508 mm (0.020 in)
• 0.635 mm (0.025 in)
• 0.762 mm (0.030 in)
• 0.899 mm (0.035 in)
• 1.016 mm (0.040 in)
• 1.143 mm (0.045 in)
• 1.270 mm (0.050 in)
• 1.397 mm (0.055 in)
• 1.524 mm (0.060 in)