Pontiac FIREBIRD 1972 Service Manual page 362

4B-6 1972 PONTIAC SERVICE MANUAL
4
A A N D B SERIES (2 pinion or 4 pinion) A N D G
SERIES ( 4 pinion)
Before disassembling differential case, inspect differ-
ential side bearings for visible damage of rollers and
outer races.
Place one outer race onto its matched inner race and
roller assembly and turn slowly, applying hand load.
If bearing outer race turns smoothly and no visible
damage is found, bearing can be reused.
Repeat above operation with. other race and matched
bearing and check for smoothness.
NOTE: Both side bearings and their outer races
are matched parts. I f either bearing is to be
replaced, its matching outer race must also be
replaced.
Inspect fit of inner races on case hubs by prying
against shoulders at puller recesses. Bearing inner
races must be tight on case hubs. If either bearing is
loose on case, entire case must be replaced.
If bearing inspection indicates that bearings should
be replaced, remove side bearings by using side bear-
ing puller
J 8107 (two pinion) or J 22888 (four pinion)
and adapter
J 8107-2 (Fig. 4B-4).
CAUTION: Make certain that ends of puller
arms are fully against inner race o f bearing.
Turn differential case in vise and remove other side
bearing in same manner.
C A UTI 0 N: Ring gear to case bolts have left
hand threads.
Fig. 4 8 - 7 Paint on Alignment Marks Before Disassembly
8. If removing ring gear, clamp case in vise so jaws are
90" to pinion shaft holes and remove ten ring gear
retaining bolts.
9. Partially install two bolts on opposite sides of ring
gear.
10. Remove ring gear from case by alternately tapping on
bolts.
CAUTION: Do not pry bet ween case and ring
gear.
11. Scribe mark or paint differential case halves (Fig.
4B-7) to aid in alignment of case when assembling.
12. Remove differential case half attaching bolts.
NOTE: Shims are used in some units between
the sidegear and cone to maintain proper back-
lash between pinion gears and side gears. Keep
these parts with cap half o f case assembly after
disassembly.
13. Lift cap half of case from flange half. Remove clutch
cone, side gear, spring block, preload springs and
shims, if provided.
14. Remove corresponding parts from flange half of case
and keep them with flange half of case assembly.
CLEANING A N D INSPECTION OF CASE
-
B SERIES
( 0 CODED AXLE)
Thoroughly clean differential case and inspect, pay-
ing particular attention to ring gear mounting flange,
ring gear pilot and side bearing hubs.
Remove nicks and burrs with mill file.
NOTE: I f using new case, thoroughly clean case
in suitable solvent, making certain bolt holes
and bolts are clean of steel filing and foreign
material.
Clean side gears, pinion gears and thrust washers
with suitable solvent and inspect for excessive wear.
Clean side bearings thoroughly in clean solvent (do
not use a brush). Examine bearings visually and by
feel. Bearings should feel smooth when oiled and
rotated, while applying as much hand pressure as
possible. Minute scratches and pits that appear on
rollers and races at low mileage are due to the initial
preload. Bearings having these marks should not be
rejected.
Thoroughly clean ring gear and inspect back side for
any adhering material which may cause runout.