Chevrolet 1988 Light Duty Truck Repair Manual page 218

4B5-26 DANA REAR AXLES
1. A ssem ble the differential case (22) with master
bearings installed to the axle housing. The pinion
must be installed.
2. Install the spacer (used before) between the master
bearing and the axle housing.
3. M ount a dial indicator having a minim um travel of
0.200-inch with a m agnetic base on the ring gear
bolt side of the housing (figure 77).
4. Place the indicator tip on the chalk mark made
earlier.
5. Force the ring gear into mesh with the pinion. Rock
the ring gear to allow the teeth of the gears to mesh.
6. With the force still applied to the differential case,
set the dial indicator to zero.
7. Force the differential case away from the pinion
gear to obtain an indicator reading. Repeat this
action until a consistent reading is obtained.
8. Remove the indicator and the differential case from
the carrier.
9. Remove the master bearings from the differential
case.
10. Using the total shim pack size determ ined earlier,
(refer to " Determ ining Total Differential Shim Pack
Size" in this section) subtract the reading found in
step 7 from the total reading. The reading found in
step 7 will be the shim size on the ring gear side.
The rem aining portion of the shim pack will be used
on the side opposite the ring gear. Add an additional
0.015-inch worth of shim for differential bearing
preload and backlash.
11. Place the proper shim s on the differential side
b e a rin g h ub (rin g g e a r s id e ) and d riv e th e
differential bearing onto the hub using J 23690 and
J 8092 (figure 78).
• If installing a new bearing, be certain that it is
the same width as the old bearing.
12. Determine the proper size of the shim pack by
subtracting the spacer size from the rem aining
amount of shim s necessary (determined in
step 10).
13. Place the proper shims on the differential side
bearing hub (ring gear side) and drive the
differential bearing onto the hub using J 23690
and J 8092.
• If installing a new bearing, be certain that it is
the same width as the old bearing.
14. Assemble J 24385-01 to the axle housing as shown
in figure 79.
15. Assemble the dial indicator as shown in figure 161.
Preset the gage at least 0.020-inch, and then rotate
the indicator housing to zero the dial.
NOTICE: Do n o t s p re ad the d iffe re n tia l carrie r
m o r e t h a n 0 . 3 8
O v e r - s p r e a d in g th e c a r r ie r c an d a m a g e o r
d is to rt the carrier.
16. S p re a d th e c a rr ie r w h ile e x a m in in g th e d ia l
indicator.
17. Remove the dial indicator.
18. Place the bearing cups (20) onto the bearings.
19. Install the differential assem bly into the carrier
(figure 80).
m m ( 0 . 0 1 5 - i n c h ) .
20. Drive the outboard spacers (43) into the proper
sides using C-4205 and C-4171.
21. Remove the spreader.
22. In sta ll the be a rin g caps (18) in th e ir o rig in a l
positions.
23. Install the bearing cap bolts (19).
T ig h ten
The bearing cap bolts (19) to 115 N m (85 ft.
lbs.).
CHECKING BACKLASH
1. Mount a dial indicator with a m agnetic base to the
axle housing as shown in figure 81.
2. Place the indicator tip at the heel end of the tooth.
3. Check the backlash at three equally spaced points.
T h e b a c k la s h s h o u ld
(0.005-0.009-inch). The m easurem ent must not vary
more than 0.05 mm (0.002-inch) between the points
checked.
4. High backlash is corrected by moving the ring gear
closer to the pinion.
5. Low backlash is corrected by moving the ring gear
away from the pinion.
6. To adjust the backlash, the differential case must be
removed from the housing, then the differential
bearings removed, and the proper num ber of shims
moved from one side to the other.
FINAL ASSEMBLY
Install or C onnect
Drive axles. Refer to the proper service manual.
RTV to the axle cover.
Axle cover (14) to the housing (figure 82).
T ig h ten
• The cover bolts (17) to 47 N m (35 ft. lbs.).
Axle housing to the vehicle. Refer to the proper
service manual.
Lubricant to the rear axle after the RTV has cured.
be 0 .1 3 -0 .2 3 mm