Installation And A D Ju Stm En T; Drive Pin Io N; Removal; Disassembly - GMC 1982 Light Duty Truck Service Manual

4 B 2 -6 R EA R A X L E
Fig. 4B2-12--Measuring Backlash
3. Torque bolts alternately to specifications.
Disassem bly o f Case
1. M ark the case and cover halves with a scribe line for
reassembly in the same position.
2. W ith ring gear removed, separate case and cover.
3. Remove the internal parts and keep separated so they
may be installed in the same relative positions.

Inspection

1. Inspect the differential gears, pinions, thrust washers,
spider and all mating surfaces for evidence of abnormal
wear.
2. Clean all parts thoroughly in suitable solvent.
3. Replace parts as necessary.
Reassembly o f D iffe re n tia l
1. Lubricate internal parts with hypoid gear lubricant.
2. Place differential pinions and th ru st washers onto
spider.
3. Assemble differential gears and washers to case and
cover.
4. A ssemble differential case and cover m aking sure
scribe marks align.
5. Install ring gear and attaching bolts and lockwashers
and torque alternately to specifications.
6. The differential may be installed into the carrier at this
point, or may be installed after servicing the drive
pinion.
In s ta lla tio n a n d A d ju s tm e n t
1. Place bearin g cups over side bearings and lift the
differential assembly into the carrier. Install bearing
caps, making sure marked caps are installed in original
positions. Secure the cap bolts snugly.
2. Loosen the right side adjusting nut and tighten the left
side nut, using J-24429 as shown in figure 4B2-9, until
the ring gear contacts the drive pinion. Do not force the
gears into contact so as to bind them. At this point, zero
lash is obtained.
3. Back off the left adjusting nut approximately two slots.
Install locking fingers into holes and fasten fingers to
bearing cap.
4. Tighten right adjusting nut firmly to force the case into
solid contact with the left adjusting nut.
5. Loosen right adjusting nut until it is free from its
bearing, then retighten until it contacts the bearing.
6. Tighten right adjusting nut approximately two slots if
used bearings are being installed, or three slots if new
bearings are being installed.
7. Install locking retainer into holes and attach fingers to
bearing cap.
8. Torque bearing cap bolts to specifications. At this point
the differential bearings are properly preloaded. If any
additional adjustments are required in the following
procedures, make sure that the preload remains as
established. If one adjusting nut is loosened, the other
nut must be tightened
preload.
9. M ount a dial indicator on the housing and m easure
th e b a c k la sh b e tw e e n the ring g e a r a nd pinion.
Backlash should be from .003" to .012" with .005" to
.008" preferred. Refer to figure 4 B 2 -12.
If backlash is more than .012", loosen the right adjust­
ing nut one slot and tighten left adjusting nut one slot.
If backlash is less than .003", loosen the left adjusting
nut one slot and tighten the right adjusting nut one
slot.
DRIVE P IN IO N ASSEMBLY

Removal

1. Remove differential as previously outlined.
2. C heck pinion bearing preload as described under
" Drive Pinion - R e assem bly". Record the result. If
there is no preload reading, ch e c k for looseness of
pinion assem bly by shaking the com panion flange.
L o oseness indicates the need for bearing replace­
ment.
3. Remove the pinion bearing retainer bolts from the
housing as shown in figure 4 B 2 -13.
4. Remove the pinion and bearing retainer assembly. It
may be necessary to rap on the pilot end of the pinion to
assist the assembly from the carrier.
5. Record the thickness of the shims removed from
between the bearing retainer flange and the carrier
housing.

Disassembly

1. Clam p the pinion assembly in vise.
2. Install Holder J -8 6 14-11 on flange by using two bolts
with flat washers, as shown in figure 4B2-14. Position
J - 8 6 14-11 on flange so that the four notches are toward
the flange.
3. Use a suitable sized socket to remove the pinion nut and
washer. Discard the pinion nut and use a new one upon

reassembly.

4. Thread end of J - 8 6 14-3 into small O.D. end of J - 8 6 14-
2. Then with J - 8 6 14-11 installed as a step 2, insert
J - 8 6 14-2 into J - 8 6 14-11 and turn it 1/8 of a turn to
locked position. Remove flange by turning J - 8 6 14-3
while holding J - 8 6 14-11 as shown in figure 4 B 2-15.
5. Su ppo rt the bearing retainer as shown in figure
an equal amount to maintain this