Jeep 1997 Grand Cherokee Service Manual page 136

ARBOR DISC PINION HEIGHT BLOCK
3 - 78 DIFFERENTIAL AND DRIVELINE
ADJUSTMENTS (Continued)
Fig. 74 Gauge Tools In Housing—Typical
ple, if the depth variance is –2, add +0.002 in. to the
dial indicator reading.
Fig. 75 Pinion Gear Depth Measurement—Typical
(10) Remove the pinion depth gauge components
from the axle housing
DIFFERENTIAL BEARING PRELOAD AND GEAR
BACKLASH
Differential side bearing preload and gear backlash
is achieved by selective shims inserted between the
bearing cup and the axle housing. The proper shim
thickness can be determined using slip-fit dummy
bearings D-348 in place of the differential side bear-
ings and a dial indicator C-3339. Before proceeding
with the differential bearing preload and gear back-
lash measurements, measure the pinion gear depth
and prepare the pinion gear for installation. Estab-
lishing proper pinion gear depth is essential to estab-
lishing gear backlash and tooth contact patterns.
After the overall shim thickness to take up differen-
tial side play is measured, the pinion gear is
installed, and the gear backlash shim thickness is
ARBOR DIAL INDICATOR SCOOTER BLOCK PINION BLOCK ARBOR
measured. The overall shim thickness is the total of
the dial indicator reading, starting point shim thick-
ness, and the preload specification added together.
The gear backlash measurement determines the
thickness of the shim used on the ring gear side of
the differential case. Subtract the gear backlash shim
thickness from the total overall shim thickness and
select that amount for the pinion gear side of the dif-
ferential (Fig. 76).
Fig. 76 Axle Adjustment Shim Locations
SHIM SELECTION
NOTE: It is difficult to salvage the differential side
bearings during the removal procedure. Install
replacement bearings if necessary.
(1) Remove side bearings from differential case.
(2) Install ring gear, if necessary, on differential
case and tighten bolts to specification.
(3) Install dummy side bearings D-348 on differen-
tial case.
(4) Install differential case in axle housing.
(5) Insert Dummy Shims 8107 (0.118 in. (3.0 mm))
starting point shims between the dummy bearing
and the axle housing (Fig. 77).
(6) Install the marked bearing caps in their correct
positions. Install and tighten the bolts.
(7) Thread guide stud C-3288-B into rear cover
bolt hole below ring gear (Fig. 78).
(8) Attach dial indicator C-3339 to guide stud.
Position the dial indicator plunger on a flat surface
on a ring gear bolt head (Fig. 78).
(9) Push firmly and hold differential case to pinion
gear side of axle housing.
(10) Zero dial indicator face to pointer.
(11) Push firmly and hold differential case to ring
gear side of the axle housing.
(12) Record dial indicator reading.
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