Pontiac FIREBIRD 1972 Service Manual page 348

4A-24 1972 PONTIAC SERVICE MANUAL
Fig. 4 A - 3 6 Pinion Shim
1 1. Remove pinion gauge assembly and both bearings
from case.
12. Slide pinion shim onto pinion shaft and install rear
pinion (Fig. 4A-36) bearing on pinion, using installer
J 8609 (B Series), J 21022 (A or G Series) and holder
J 6407-1 and 2 in a press, as shown in Fig. 4A-37.
PINION ASSEMBLY
REPLACE PINION ASSEMBLY AND ADJUST
PINION PRELOAD
1. Examine ring gear and pinion for nicks, burrs or
scoring. Any of these conditions will require replace-
ment of gear set.
Position pinion assembly in carrier and install new
collapsible spacer. Tap rear of pinion assembly with
soft hammer to assure seating of rear pinion bearing
to its outer race in carrier.
Place front pinion bearing in position on pinion. Hold
pinion fully forward and drive bearing over pinion
until seated, using installer J 21285-01.
Coat O.D. of pinion oil seal with sealing compound
and install in carrier, using installer J 21285-01 (A
and G Series) or J 22388 (B Series) (Fig. 4A-10).
Coat lips of pinion oil seal and seal surface of com-
panion flange with gear lube. Install companion
flange on pinion, by tapping with a soft hammer until
a few pinion threads project through flange.
Install pinion washer and nut. Hold companion
flange with holder J 8614-10. While intermittently
rotating pinion to seat bearings, tighten pinion nut
until end play begins to be taken up.
CAUTION: When no further end play can be
determined, and holder J 8614-10 will no
longerpivot freely as pinion is rotated, preload
is being applied. Further tightening should be
done only after preload has been checked.
Check preload by using a lb. in. torque wrench (Fig.
CAUTION: Afterpreload has been checked,
fi-
nal 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 fir and require its replacement.
Backing offnut to correct excessive preload will
unload the front bearing and pinion nut, a110 w-
ing beanng to turn on shaft.
8. While observing the preceding caution, carefully set
preload drag to 25 lb. in. on new bearings or 17 lb.
in. on used bearings.
Fig. 4A-37 Installing Rear Pinion Bearing
Fig. 4 A - 3 8 Checking Pinion Bearing Preload