010 -Inch - GMC 1990 Light Truck Repair Manual

4B7-4 LOCKING DIFFERENTIALS
11. If the backlash is too low, use a thinner thrust
washer.
Right Side Gear Backlash Adjustment
1. Assemble the clutch plates.
• Alternate the plates as shown in figure 1.
2. Assemble the guide clips (19) to the plates.
• Use grease in the clips to hold them in place
on the plates.
3. Install the thrust washer (
(9), and right side gear to the differential.
4. Place the pinion gears (7) and thrust washers (
into the differential.
• Align them with the pinion shaft hole.
5. Press down the side gear, and install the pinion
shaft (18) and lock screw (3).
• If the side gear cannot be pressed down far
enough to install the pinion shaft, replace the
thrust washer with a thinner washer.
6
. Rotate the pinion gear closest to the lock screw so
that one of the teeth is pointing downward
(perpindicular to the ring gear flange).
7. Insert a large tapered tool such as a screwdriver
firmly between the side gear and the pinion shaft.
8
. Mount a dial indicator to the ring gear flange, and
place the stem of the indicator on one of the teeth
on the pinion gear closest to the lock screw (figure
5).
9. Pull the pinion gear firmly into its seat, and rotate
the gear back and forth while reading the dial
indicator. Record the reading.
6
10. Repeat steps through 9 on the opposite pinion
gear.
11
. The backlash should be between 0.051 and 0.243
0.002 0 010
mm ( - . -inch).
12. If the backlash is too high, use a thicker thrust
washer.
13. If the backlash is too low, use a thinner thrust
washer.
Thrust Block Clearance Adjustment
Install or Connect
Left thrust washer (13) to the differential.
Cam unit to the differential.
8
Right thrust washer (
Clutch plates with guide clips to the differential.
• Assemble alternatively as shown in figure 1.
Right side gear (10) to the differential.
Pinion shaft (18) and lock screw (3). Insert a large
tapered tool such as a screwdriver firmly between
each side gear and the pinion shaft.
A 1 to 2-inch telescoping gage between the side
gear faces, not the gear teeth.
• Measure the side gear spread (figure
Measure
M
Remove the telescoping gage.
Measure the telescoping gage with a micrometer.
Measure the original thrust block at the outer corner
with a micrometer (figure 7).
If the thrust block thickness is not 0.000 to
0.006-inch less than the side gear spread, adjust the
clearance by:
8
), clutch plate assembly
) to the differential.
6
).
6
)
Figure 6—Measuring Side Gear Spread
— Selecting a new thrust block the correct size to
0.000
obtain
— Reshiming the right and/or left clutch disk
pack. The backlash must remain
0 010
. -inch.
ASSEMBLY OF THE DIFFERENTIAL
Install or Connect (Figure 1)
1
. Left thrust washer (13).
2. Cam unit. Refer to "Cam Unit Assembly" in this
section.
3. Right thrust washer (
4. Right clutch plates with guide clips (19).
• Assembly alternatively as shown in figure 1.
5. Right side gear (10).
6
. Thrust block (17), thrust washer (
(7).
• Place the pinion gears into the differential 180
degrees apart.
• Rotate the gears and thrust block into position.
F-04803
to 0.006-inch clearance.
0.002
8
).
6
), and pinion gear
-