Automatic Locking Hub Service - GMC G Service Manual

Clean
• The bearings and yokes.
Inspect
• The bearings and yokes. Replace parts as
necessary.
H Install or Connect (Figure 2)
• Lubricate the new bearings with the recommended
universal joint lubricant. Refer to MAINTENANCE
AND LUBRICATION (SEC. OBj:
1. Bearing cup in a yoke ear.
2. U-joint in the bearing cup.
3. Another bearing cup in the opposite yoke ear with the
U-joint aligned.
4. Bearing cup in each ear of the companion yoke.
• Press the bearing cups in beyond the lock ring
grooves.
5. Lock ring at each bearing cup.
• Tap the yoke lightly to seat the bearings against
the lock rings.
• Lubricate the U-joint with the recommended lubricant
through the fitting provided. Refer to MAINTENANCE
AND LUBRICATION (SEC. OB).
AUTOMATIC LOCKING
HUB SERVICE
LOCKING UNIT REMOVAL
H Remove or Disconnect (Figure 4)
1. Screws (50) and O-ring seals (51).
2. Cover (52).
3. Spring (54).
4. Bearing assembly, consisting of the inner race (55),
the bearing (56) and retainer (58).
5. Seal (53).
6. Keeper (60) from the outer clutch housing (59).
7. Ring (57) to release the locking unit. Remove the ring
by compressing it with needle nose pliers.
8. Locking unit from hub.
To facilitate removal, loosely thread two cover
screws (50) into the outer clutch housing (59)
perimeter, and use them to withdraw the unit.
If a wheel bearing adjustment is necessary, refer to the
adjustment procedure specific to four wheel drive vehicles
in FRONT SUSPENSION AND AXLE (SEC. 3C).
LOCKING UNIT DISASSEMBLY
Disassemble (Figure 4)
1. Retaining ring (77) and spacer (76) from inboard end
of hub sleeve (67).
2. Drag sleeve (75)/brake band (74) assembly.
Rotate assembly until it releases from the lock­
ing unit.
FRONT DRIVING AXLE 4C-5
] Important
NEVER REMOVE THE BRAKE BAND (74)
FROM THE DRAG SLEEVE (75). The spring
tension of the brake band (74) could be
changed if the coils are over expanded. The
operation of the hub could also be affected.
3. Brake band retainer (A).
Use care while removing, so that the metal
doesn't become deformed.
4. Ring (73) from the groove in the outer clutch housing
(59).
• Position the unit so that the end containing the inner
cage (72) is face down on the bench.
5. Snap ring (61), which will release the return spring
(64), the retainers (63 and 65) and the retainer plate
(62).
• Position the opposite end of the unit on a 1 7/16-inch
socket.
• Press downward on the top perimeter of the assem­
bly to expose the white plastic tab of the outer cage
(71) which is seated in the inner cage (72) port.
6. Inner cage (72). Pry the plastic tab of the outer cage
(71) from the port of the inner cage (72).
If excessive force is used, the plastic cage may
deform or break.
7. Outer cage (71).
8. Cam follower. Pry the Ifegs of the cam follower (70)
from the flats of the clutch gear (66) to release the
hub sleeve (67) and the conical spring (69).
9. Outer clutch housing (59).
10. Stop ring (68) from the hub sleeve (67) shaft.
LOCKING UNIT ASSEMBLY
Assemble (Figure 4)
\ M
1. Conical spring (69), seating the smaller end against
the cam follower (70).
2. Hub sleeve (67).
Pack sleeve with a lubricant such as GM part
no. 1052750, or equivalent.
3. Clutch gear (66), over the splines of the hub sleeve
(67).
4. Cam follower (70), hooking the legs onto the flats of
the clutch gear (66).
Lubricate the outer splines of the hub sleeve
(67) with GM part no. 1052750, or equivalent.
] Important
The gear (66) and spring (69) should slide freely
over the splines of the sleeve (67).
5. Stop ring (68) to the hub sleeve (67).
6. Sleeve (67)/clutch gear (66) assembly into the outer
clutch housing (59).
7. Outer cage (71), seating it under the rim of the outer
clutch housing (59).