Adjustments Affecting Tooth Contact - Isuzu 1999 RODEO Workshop Manual

4A2–24 DIFFERNTIAL (REAR)
425RS039

Adjustments Affecting Tooth Contact

Two adjustments can be made which will affect tooth
contact pattern: backlash, and the position of the drive
pinion in the case. The effects of bearing preloads are not
readily apparent on head loaded tooth contact pattern
tests; however, these adjustments shuld be within
specifications before proceeding with backlash and drive
pinion adjustments.
The position of the drive pinion is adjusted by increasing
or decreasing the distance between the pinion head and
the centerline of the ring gear.
Decreasing the distance will move the pinion closer to the
centerline of the ring gear. Increasing the distance will
move the pinion farther away from the centerline of the
ring gear.
Backlash is adjusted by means of the side bearing
adjusting shims which move the entire case and ring gear
assembly closer to, or farther from, the drive pinion. (The
adjusting shims are also used to set side bearing
preload.)
If the thickness of the right shim is increased (along with
decreasing the left shim thickness), backlash will
increase.
The backlash will decrease if the left shim thickness is
increased (along with a decrease in right shim thickness).