Replace Differential Case And Adjust Side Bearing Preload; Pinion Shim - Pontiac Grand Prix Service Manual

STANDARD DIFFERENTIAL 4A-23
Fig. 4A-41 Pinion Shim
3. Coat O.D. of pinion oil seal with sealing compound
and install in camer, using installer J 21285-01 (Fig.
4A-9).
4. Coat lips of pinion oil seal and seal surface of
companion flange with gear lube. Install companion
flange on pinion, by tapping with a soft hammer until
a few pinion threads project through flange.
5. Install pinion washer and nut. Hold companion
flange with holder J
86 14- 1. While intermittently
rotating pinion to seat bearings, tighten pinion nut
until end play begins to be taken up.
CA UTION: When no further end play can be deter-
mined, and holder J 8614-1 will no longer pivot freely as
pinion is rotated preload is being applied. Further
tightening should be done only after preload has been
checked.
6. Check preload by using a Ib. in. torque wrench (Fig.
4A-43).
CA UTION: After preload has been checked, final
tightening should be done very cautiously. Tighten the
pinion nut further, only a little at a time, and check
preload after each slight amount of tightening.
Exceeding preload specifications will compress the
collapsible spacer too far and require its replacement.
Backing off nut to correct excessive preload will unload
the fiont bearing and pinion nut, allowing bearing to
turn on shaji.
7. While observing the preceding caution, carefully set
preload drag to 25 Ib. in. on new bearings or 17 Ib. in.
on used bearings.
8. Rotate pinion several times to assure that bearings
have been seated. Check preload again. If drag has
been reduced by rotating pinion, re,set preload to
specification.
REPLACE DIFFERENTIAL CASE AND ADJUST SIDE
BEARING PRELOAD
Production shims are cast iron and vary in thickness
from .210" to .272", in increments of .002".
Fig. 4A-43 Checking Pinion Bearing Preload
Fig. 4A-42 Installing Rear Pinion Bearing Fig. 4A-44 Measuring Original Production Shim