
SPECIAL TOOLS
SUSPENSION-REAR
BUSHINGS
REMOVAL
(1) Remove the spring from the vehicle.
(2) Position the spring eye in a press.
(3) Press the bushing out with an appropriate size
driver.
INSTALLATION
(1) Press new bushing into the spring eye with an
appropriate size driver. The bushing should be cen-
tered in the spring eye.
(2) Install the spring on the vehicle.
SHOCK
REMOVAL
(1) Raise vehicle and support axle.
(2) Remove the bolt and flag nut from the frame
crossmember bracket (Fig. 1).
(3) Remove the bolt and nut from the axle bracket.
(4) Remove the rear shock absorber from the vehi-
cle.
INSTALLATION
(1) Position the shock absorber in the brackets.
(2) Install the bolts through the brackets and the
shock. Install the flag nut on the top bolt and nut on
lower bolt.
(3) Tighten the upper and lower bolt/nuts Tighten
to 136 N.m (100 ft. lbs.)
(4) Remove the support and lower the vehicle.
SPRING
REMOVAL
(1) Raise the vehicle and support the axle to
remove all weight from the springs.
(2) Remove the nuts and spring clamp bolts that
attach the spring to the axle (Fig. 2) and (Fig. 3)and
(Fig. 4).
(3) Remove the nuts and bolts from the spring
front and rear shackle eyes.Note: To remove front
eye bolt on left side spring fuel tank must be
removed, (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/FUEL TANK - REMOVAL).
(4) Remove the spring from the vehicle.
(5) Remove the shackle from the spring.
Puller C-3894-A
Fig. 1 Shock Absorber
1 - FLAG NUT
2 - AXLE
3 - SHOCK
BR/BEREAR 2 - 27
REAR (Continued)

INSTALLATION
(1) Install shackle on rear spring eye and install
bolt and nut.(2) Position spring on axle shaft tube so spring
center bolt is inserted into the locating hole in the
axle tube spring pad or spacer.
(3) Align spring front eye with bolt hole in the
front bracket. Install the eye pivot bolt and nut.
(4) Align shackle eye with bolt hole in rear
bracket. Install bolt and nut.
(5) Tighten the spring front and rear eye pivot bolt
snug do not torque.
(6) Install spring clamp bolts and the retaining
nuts.
(7) Align the auxiliary spring with the primary
spring if equipped. Tighten the nuts until they force
the plate flush against the axle tube.
(8) Remove the supports and lower the vehicle so
that the weight is being supported by the tires.
(9) Tighten the spring clamp retaining nuts to
specifications
(10) Tighten spring front and rear eye pivot bolt
nuts and shackle eye to specifications.
Fig. 2 Rear Spring - 4x2
1 - SPRING CLAMP BOLTS
2 - SPRING SEAT
3 - SPRING
4 - SHACKLE
5 - SPRING PLATE
Fig. 3 Rear Spring - 4x4
1 - SPRING CLAMP BOLT
2 - SPRING SEAT
3 - SPRING
4 - SHACKLE
5 - SPRING PLATE
6 - SPACER
Fig. 4 Rear Spring - Cab-Chassis 11000 GVW
1 - SPRING CLAMP BOLT
2 - SPRING SEAT
3 - AUXILIARY SPRING
4 - SPRING
5 - SHACKLE
6 - SPRING PLATE
7 - SPACER
2 - 28 REARBR/BE
SPRING (Continued)

DRIVELINE VIBRATION
Drive Condition Possible Cause Correction
Propeller Shaft Noise 1) Undercoating or other foreign
material on shaft.1) Clean exterior of shaft and wash
with solvent.
2) Loose U-joint clamp screws. 2) Install new clamps and screws
and tighten to proper torque.
3) Loose or bent U-joint yoke or
excessive runout.3) Install new yoke.
4) Incorrect driveline angularity. 4) Measure and correct driveline
angles.
5) Rear spring center bolt not in
seat.5) Loosen spring u-bolts and seat
center bolt.
6) Worn U-joint bearings. 6) Install new U-joint.
7) Propeller shaft damaged or out
of balance.7) Installl new propeller shaft.
8) Broken rear spring. 8) Install new rear spring.
9) Excessive runout or unbalanced
condition.9) Re-index propeller shaft, test,
and evaluate.
10) Excessive drive pinion gear
shaft runout.10) Re-index propeller shaft and
evaluate.
11) Excessive axle yoke deflection. 11) Inspect and replace yoke if
necessary.
12) Excessive transfer case runout. 12) Inspect and repair as necessary.
Universal Joint Noise 1) Loose U-joint clamp screws. 1) Install new clamps and screws
and tighten to proper torque.
2) Lack of lubrication. 2) Replace as U-joints as
necessary.
BALANCE
NOTE: Removing and re-indexing the propeller
shaft 180É relative to the yoke may eliminate some
vibrations.
If propeller shaft is suspected of being unbalanced,
it can be verified with the following procedure:
(1) Raise the vehicle.
(2) Clean all the foreign material from the propel-
ler shaft and the universal joints.
(3) Inspect the propeller shaft for missing balance
weights, broken welds and bent areas.If the propel-
ler shaft is bent, it must be replaced.
(4) Inspect the universal joints to ensure that they
are not worn, properly installed and correctly aligned
with the shaft.
(5) Check the universal joint clamp screws torque.
(6) Remove the wheels and tires. Install the wheel
lug nuts to retain the brake drums or rotors.
(7) Mark and number the shaft six inches from the
yoke end at four positions 90É apart.(8) Run and accelerate the vehicle until vibration
occurs. Note the intensity and speed the vibration
occurred. Stop the engine.
(9) Install a screw clamp at position 1 (Fig. 1).
(10) Start the engine and re-check for vibration. If
there is little or no change in vibration, move the
clamp to one of the other three positions. Repeat the
vibration test.
(11) If there is no difference in vibration at the
other positions, the source of the vibration may not
be propeller shaft.
(12) If the vibration decreased, install a second
clamp (Fig. 2) and repeat the test.
(13) If the additional clamp causes an additional
vibration, separate the clamps (1/2 inch above and
below the mark). Repeat the vibration test (Fig. 3).
(14) Increase distance between the clamp screws
and repeat the test until the amount of vibration is
at the lowest level. Bend the slack end of the clamps
so the screws will not loosen.
3 - 2 PROPELLER SHAFTBR/BE
PROPELLER SHAFT (Continued)

LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side-gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by:
²Damaged drive shaft.
²Missing drive shaft balance weight(s).
²Worn or out of balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front end components
or engine/transmission mounts. These components
can contribute to what appears to be a rear end
vibration. Do not overlook engine accessories, brack-
ets and drive belts.All driveline components should be examined
before starting any repair.
(Refer to 22 - TIRES/WHEELS - DIAGNOSIS AND
TESTING)
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged) can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
DIAGNOSTIC CHART
Condition Possible Causes Correction
Wheel Noise 1. Wheel loose. 1. Tighten loose nuts.
2. Faulty, brinelled wheel bearing. 2. Replace bearing.
Axle Shaft Noise 1. Misaligned axle tube. 1. Inspect axle tube alignment.
Correct as necessary.
2. Bent or sprung axle shaft. 2. Inspect and correct as necessary.
3. End-play in pinion bearings. 3. Refer to pinion pre-load
information and correct as
necessary.
4. Excessive gear backlash
between the ring gear and pinion.4. Check adjustment of the ring
gear and pinion backlash. Correct
as necessary.
5. Improper adjustment of pinion
gear bearings.5. Adjust the pinion bearings
pre-load.
6. Loose pinion yoke nut. 6. Tighten the pinion yoke nut.
7. Scuffed gear tooth contact
surfaces.7. Inspect and replace as
necessary.
3 - 16 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

Condition Possible Causes Correction
Axle Shaft Broke 1. Misaligned axle tube. 1. Replace the broken shaft after
correcting tube mis-alignment.
2 Vehicle overloaded. 2. Replace broken shaft and avoid
excessive weight on vehicle.
3. Erratic clutch operation. 3. Replace broken shaft and avoid
or correct erratic clutch operation.
4. Grabbing clutch. 4. Replace broken shaft and inspect
and repair clutch as necessary.
Differential Cracked 1. Improper adjustment of the
differential bearings.1. Replace case and inspect gears
and bearings for further damage.
Set differential bearing pre-load
properly.
2. Excessive ring gear backlash. 2. Replace case and inspect gears
and bearings for further damage.
Set ring gear backlash properly.
3. Vehicle overloaded. 3. Replace case and inspect gears
and bearings for further damage.
Avoid excessive vehicle weight.
4. Erratic clutch operation. 4. Replace case and inspect gears
and bearings for further damage.
Avoid erratic use of clutch.
Differential Gears Scored 1. Insufficient lubrication. 1. Replace scored gears. Fill
differential with the correct fluid type
and quantity.
2. Improper grade of lubricant. 2. Replace scored gears. Fill
differential with the correct fluid type
and quantity.
3. Excessive spinning of one
wheel/tire.3. Replace scored gears. Inspect all
gears, pinion bores, and shaft for
damage. Service as necessary.
Loss Of Lubricant 1. Lubricant level too high. 1. Drain lubricant to the correct
level.
2. Worn axle shaft seals. 2. Replace seals.
3. Cracked differential housing. 3. Repair as necessary.
4. Worn pinion seal. 4. Replace seal.
5. Worn/scored yoke. 5. Replace yoke and seal.
6. Axle cover not properly sealed. 6. Remove, clean, and re-seal
cover.
Axle Overheating 1. Lubricant level low. 1. Fill differential to correct level.
2. Improper grade of lubricant. 2. Fill differential with the correct
fluid type and quantity.
3. Bearing pre-loads too high. 3. Re-adjust bearing pre-loads.
4. Insufficient ring gear backlash. 4. Re-adjust ring gear backlash.
BR/BEFRONT AXLE - 248FBI 3 - 17
FRONT AXLE - 248FBI (Continued)

Condition Possible Causes Correction
Gear Teeth Broke 1. Overloading. 1. Replace gears. Examine other
gears and bearings for possible
damage.
2. Erratic clutch operation. 2. Replace gears and examine the
remaining parts for damage. Avoid
erratic clutch operation.
3. Ice-spotted pavement. 3. Replace gears and examine
remaining parts for damage.
4. Improper adjustments. 4. Replace gears and examine
remaining parts for damage. Ensure
ring gear backlash is correct.
Axle Noise 1. Insufficient lubricant. 1. Fill differential with the correct
fluid type and quantity.
2. Improper ring gear and pinion
adjustment.2. Check ring gear and pinion
contact pattern.
3. Unmatched ring gear and pinion. 3. Replace gears with a matched
ring gear and pinion.
4. Worn teeth on ring gear and/or
pinion.4. Replace ring gear and pinion.
5. Loose pinion bearings. 5. Adjust pinion bearing pre-load.
6. Loose differential bearings. 6. Adjust differential bearing
pre-load.
7. Mis-aligned or sprung ring gear. 7. Measure ring gear run-out.
Replace components as necessary.
8. Loose differential bearing cap
bolts.8. Inspect differential components
and replace as necessary. Ensure
that the bearing caps are torqued
tot he proper specification.
9. Housing not machined properly. 9. Replace housing.
REMOVAL
(1) Raise and support the vehicle.
(2) Remove wheels and tires.
(3) Remove brake calipers and rotors. Refer to 5
Brakes for procedures.
(4) Remove ABS wheel speed sensors, if equipped.
Refer to 5 Brakes for procedures.
(5) Disconnect axle vent hose.
(6) Disconnect vacuum hose and electrical connec-
tor at disconnect housing.
(7) Remove front propeller shaft.
(8) Disconnect stabilizer bar links at the axle
brackets.
(9) Disconnect shock absorbers from axle brackets.
(10) Disconnect track bar from the axle bracket.
(11) Disconnect tie rod and drag link from the
steering knuckles.
(12) Position suitable lifting device under the axle
assembly.(13) Secure axle to lifting device.
(14) Mark suspension alignment cams for installa-
tion reference.
(15) Disconnect upper and lower suspension arms
from the axle bracket.
(16) Lower the axle. The coil springs will drop
with the axle.
(17) Remove the coil springs from the axle bracket.
INSTALLATION
CAUTION: Suspension components with rubber
bushings should be tightened with the weight of the
vehicle on the suspension, at normal height. If
springs are not at their normal ride position, vehicle
ride comfort could be affected and premature bush-
ing wear may occur. Rubber bushings must never
be lubricated.
(1) Support the axle on a suitable lifting device.
3 - 18 FRONT AXLE - 248FBIBR/BE
FRONT AXLE - 248FBI (Continued)

cle turns. A worn pinion shaft can also cause a snap-
ping or a knocking noise.
BEARING NOISE
The axle shaft, differential and pinion bearings can
all produce noise when worn or damaged. Bearing
noise can be either a whining, or a growling sound.
Pinion bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
noise will be higher pitched because it rotates at a
faster rate. Drive the vehicle and load the differen-
tial. If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually pro-
duce a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differen-
tial bearing noise is also constant and varies only
with vehicle speed.
Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side±gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by a:
²Damaged drive shaft.²Missing drive shaft balance weight(s).
²Worn or out-of-balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front-end components
or engine/transmission mounts. These components
can contribute to what appears to be a rearend vibra-
tion. Do not overlook engine accessories, brackets
and drive belts.
NOTE: All driveline components should be exam-
ined before starting any repair.
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged), can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
3 - 48 REAR AXLE - 248RBIBR/BE
REAR AXLE - 248RBI (Continued)

DIAGNOSTIC CHART
Condition Possible Causes Correction
Wheel Noise 1. Wheel loose. 1. Tighten loose nuts.
2. Faulty, brinelled wheel bearing. 2. Replace bearing.
Axle Shaft Noise 1. Misaligned axle tube. 1. Inspect axle tube alignment.
Correct as necessary.
2. Bent or sprung axle shaft. 2. Inspect and correct as necessary.
Axle Shaft Broke 1. Misaligned axle tube. 1. Replace the broken shaft after
correcting tube mis-alignment.
2 Vehicle overloaded. 2. Replace broken shaft and avoid
excessive weight on vehicle.
3. Erratic clutch operation. 3. Replace broken shaft and avoid
or correct erratic clutch operation.
4. Grabbing clutch. 4. Replace broken shaft and inspect
and repair clutch as necessary.
Differential Cracked 1. Improper adjustment of the
differential bearings.1. Replace case and inspect gears
and bearings for further damage.
Set differential bearing pre-load
properly.
2. Excessive ring gear backlash. 2. Replace case and inspect gears
and bearings for further damage.
Set ring gear backlash properly.
3. Vehicle overloaded. 3. Replace case and inspect gears
and bearings for further damage.
Avoid excessive vehicle weight.
4. Erratic clutch operation. 4. Replace case and inspect gears
and bearings for further damage.
Avoid erratic use of clutch.
Differential Gears Scored 1. Insufficient lubrication. 1. Replace scored gears. Fill
differential with the correct fluid type
and quantity.
2. Improper grade of lubricant. 2. Replace scored gears. Fill
differential with the correct fluid type
and quantity.
3. Excessive spinning of one
wheel/tire.3. Replace scored gears. Inspect all
gears, pinion bores, and shaft for
damage. Service as necessary.
BR/BEREAR AXLE - 248RBI 3 - 49
REAR AXLE - 248RBI (Continued)