GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 1999 🢒 S/T Isuzu - 4WD 🢒 Driveline/Axle 🢒 Rear Drive Axle 🢒 Differential Carrier Bearing Preload Adjustment

Tools Required

J 22779 Side Bearing Backlash Gauge

    • The differential side bearing preload adjustment must be completed before the backlash adjustment can be started.
    • In order to maintain the original backlash, adjust the differential case side bearing preload by changing the thickness of the left and the right shims equally.
    • Measure the production shims and the spacers one at a time. Add the measurements together in order to obtain the sizes of the right and the left shim packs. Production shims are cast iron. Do not reuse production shims.
       - Service spacer thickness is nominal at 4.32 mm (0.170 in).
       - Service shims are available from 1.02-2.54 mm (0.040-0.100 in) in increments of 0.101 mm (0.004 in).
       - The side bearing surfaces must be clean and free of burrs.
  1. Place the case, with the bearing cups installed, into the axle housing.
    2. 1.1. Lubricate the axle bearings using axle lubricant.
    1.2. Support the case in order to prevent the case from falling into the axle housing.

    Object Number: 6942 Size: SH
  2. Insert the J 22779 between the axle housing and the left bearing cup.

    3. Object Number: 6943 Size: SH
  3. Turn the adjusting nut to the right until you produce a noticeable drag, while moving the tool back and forth in the bore.
    4. 3.1. Tighten the lock bolt on the side of the tool.
    3.2. Leave the tool in place.
  4. Install a service spacer and a shim between the right bearing cup and the axle housing.

    5. Insertion of progressively larger feeler gauge sizes between the axle housing and the service shim determines the bearing preload.

    4.1. Push the feeler gauge downward so that the feeler gauge contacts the shim at the top and the bottom, and then contacts the axle housing.
    4.2. The correct feeler gauge thickness is the point just before additional drag begins. This is the zero setting without the preload.
  5. Remove the following components from the vehicle:
    6. 5.1. The strap
    5.2. The J 22779
    5.3. The service spacer
    5.4. The service shim
    5.5. The feeler gauge
    5.6. The differential case from the axle housing

    Object Number: 6944 Size: SH
  6. Measure the J 22779 gauge plate thickness in three places using a micrometer. Average the readings.
  7. Add the readings of the right side service spacer, the service shim, and the feeler gauge.
  8. For the initial backlash setting, move the ring gear from the pinion by subtracting 0.25 mm (0.010 in) from the ring gear side shim pack and adding 0.25 mm (0.010 in) to the shim pack on the opposite side.
  9. In order to obtain the proper preload on the side bearings, add 0.10 mm (0.004 in) to the measurement of each shim pack.
  10. Install the differential and adjust the ring and pinion gear backlash. Refer to Backlash Adjustment .