GMC 1986 P-Truck Service Manual page 418

4C-8 FRONT AXLE
pushed inward to allow the retaining ring
(57) to expand when assem bling the
automatic locking hub to the vehicle.
AUTOMATIC HUB TO THE WHEEL
ADJUSTMENT
A lock ring (80) is supplied with each new automatic
hub assembly. Assemble this lock ring (80) between
the nut with pin (81) and the adjusting nut (79) as
follows:
Use J-6893 to torque the nut with pin (81) to
(50 ft. lbs.) to seat the wheel bearings; then back off
the nut with pin (81) and torque to 47 N m (35 ft. lbs.)
while rotating the hub (figure 3).
Then back the nut with pin (81) off a maximum of 3/8
turn. Assemble the lock ring (80) over the axle shaft
against the nut with pin (81) so that the inner tang
enters the axle shaft keyway. One of the holes in the
lock ring (80) must engage the pin on nut (81). Thread
the adjusting nut (79) onto the axle shaft and tighten to
247 N m (183 ft. lbs.).
Align the cut-outs on the drag sleeve (75) with the
tabs on the lock ring (80) as the splines of the clutch
gear (59) mesh with the splines of the wheel hub.
Loosen the five cover screws (50) three or four turns
and push in on the screws (50) to allow the ring (57) to
expand into the groove in the wheel hub. Torque the
screws (50) to 5.1 N m (45 inch lbs.).
MANUAL LOCKING HUB
REPLACEMENT
Remove or Disconnect (Figure 5)
1. Screws (91).
2. Outer hub locking assembly (92, 93, 94, 95, 96,
97, 98, and 99).
3. Snap ring (90) from the axle shaft end.
4. Internal snap ring (85) from hub.
5. Body assembly ( , 87,
86
N m
68
and 89).
88
L*
Inspect
All parts and replace as necessary.
L*
Install or Connect (Figure 5)
1. Body assembly ( , 87,
86
2. Internal snap ring (85) to the hub.
3. Snap ring (90) onto the axle shaft end.
4. Outer hub locking assembly (92, 93, 94, 95, 96,
97, 98 and 99).
5. Screws (91).
MANUAL LOCKING HUB REBUILD
PROCEDURE
• Outer hublock knob assembly should be replaced
only as a unit, because timing relationships are
difficult to restore if disassembly occurs. The
inner body may be disassembled for cleaning
and component replacement.
Remove or Disconnect (Figure 5)
Screws (91).
Hub body ( ).
86
Spring ( ).
88
Internal snap ring (85).
Inner drive gear (87) with thrust washers.
Plastic sleeve.
L*
Inspect
• All parts and replace as necessary.
Install or Connect (Figure 5)
• Lubricate inner body parts with ATF or a
light coat of wheel bearing grease.
1. Plastic sleeve.
2. Inner drive gear (87) with thrust washers.
3. Internal snap ring (85).
4. Spring ( ).
8 8
5. Hub body ( ).
8 6
. Screws (91).
6
and 89).
88