GMC 4000 Series Service Manual page 158

7. Install axle shaft as directed in "REAR
AXLES" (SEC. 4A) of this manual.
REAR HUB AND BEARING REMOVAL
(Refer to Figure 2)
1. Jack up rear axle and remove tire and rim
assembly on vehicles having cast wheels. Remove
tire and wheel assembly from trucks having vent­
ilated disc or Budd type wheels.
2. If brake drum is demountable type, remove
brake drum.
3. Remove axle shaft as directed in "REAR
AXLES" (SEC. 4A) of this manual.
TYPES D AND E
1. Remove lock nut, nut lock, and adjusting
nut from axle housing tube.
2. On Type E in figure 2, lift wheel (hub) and
drum assembly straight off axle housing, using
care to prevent outer cone and roller assembly
from dropping out of hub. Remove outer bearing
cone and roller from hub.
3. On Type D figure 2, carefully pull hub a s­
sembly straight off axle housing, using care to
prevent outer cone and roller assembly from drop­
ping out of hub. Remove outer bearing cone and
roller from hub.
4. Pull inner oil seal out of hub, then lift out
inner bearing cone and roller assembly. Discard
oil seal.
5. Clean, inspect, and repair parts as directed
later under "Cleaning, Inspection, and Repair."
TYPES A, B AND C
1. Raise tang of nut lock out of slot in lock
nut; then using wheel bearing nut wrench listed in
SPECIAL TOOLS at end of this manual, remove
lock nut.
2. Remove nut lock, bearing adjusting nut, and
washer from axle housing.
3. Carefully pull wheel (hub) and drum a s­
sembly or hub off axle housing.
4. Using a mild steel rod through outer end of
hub, drive against inner bearing cup to drive inner
cone and roller assembly and oil seal out of hub.
Drive alternately on opposite sides of cup to pre­
vent cocking of cup in hub. Discard oil seal.
5. Using a mild steel rod through inner end of
hub, tap outer bearing cup outward away from the
snap ring just enough to remove tension on snap
ring.
6. Remove the snap ring, using Tru-arc or
snap ring pliers through inner end of hub.
7. Using a mild steel rod against outer end of
axle shaft spacer, drive outer bearing out of hub.
Care must be taken to engage edge of spacer with
punch and not damage bearing seat in hub. Alter-
G M C S E R V I C E M A N U A L
nately drive on opposite sides of spacer to avoid
cocking bearing cup in hub.
CLEANING, INSPECTION, AND REPAIR
CLEANING
cleaning solvent. Clean with stiff brush if n eces­
sary to remove old lubricant. Blow bearings dry
with compressed air, directing air stream across
bearings. Do not spin bearings while blowing them
dry.
of hub and wipe dry. Make sure all particles of
gasket are removed from outer end of hub, and that
all sealing compound is cleaned out of oil seal
bore in inner end of hub.
and nut locks in cleaning solvent and wipe dry.
INSPECTION
ped edges, or other damage. Slowly roll the rollers
around cone to detect any flat or rough spots. Re­
place damaged parts. If either the cone and roller
assembly or the cup of the roller bearings are
damaged, the complete bearing assembly must be
replaced.
stalled in hub. If cups are pitted or cracked, they
must be replaced as directed later under "Repair."
which the hub inner oil seal lip wipes for evidence
of wear or roughness. If any damage is evident,
sleeve must be replaced. Oil seal sleeves are re­
placed as directed later under "Repair."
and E, figure 2) for damaged threads or bent studs.
Clean up threads or replace studs as necessary.
On Views A, B and C, figure 2, check for damaged
threads in tapped holes in outer end of hub. If
threads are damaged, holes can be filled, drilled,
and tapped, otherwise hub must be replaced. On
hubs having internal splines, check condition of
splines in outer end of hub. If any damage is evi­
dent, replace hub.
damage. Non-demountable brake drums can be re­
finished while mounted on hubs. If necessary to
replace brake drum refer to "Repair" later in this
section.
for damaged threads and replace, if necessary, as
directed later under "Repair."
seals to be used at assembly.
REAR HUBS AND BEARINGS
8. Clean, inspect, and repair parts as follows:
1. Immerse bearing assem blies in suitable
2. Thoroughly clean all lubricant out of inside
3. Clean lubricant off axle housing tube.
4. Wash small parts such as nuts, spacers,
1. Inspect bearings for excessive wear, chip­
2. Examine bearing cups which are still in­
3. Examine oil seal sleeve (when used) on
4. Examine axle shaft flange studs (Views D
5. Examine brake drums for scoring or other
6. Examine wheel studs or rim clamp studs
7. Discard old oil seals and obtain new oil
Sec. 4C
Page 151