engine DODGE RAM 2003 Service Owner's Manual

angle while adjusting caster, move one pivot bolt of
the upper control arm in or out. Then move the other
pivot bolt of the upper control arm in the opposite
direction. Install special tool 8876 between the top of
the upper control arm bracket and the upper control
arm (on 1500 series 4X2 & 4X4). Install special tool
8876 between the bottom of the upper control arm
bracket pressing the tool against the frame and the
upper control arm (on 2500/3500 series 4X2) in order
to move the upper control arm outwards for proper
adjustment with the vehicle at normal ride height
(Fig. 3).
To increase positive caster angle, move the rear
position of the upper control arm inward (toward the
engine). Move the front of the upper control arm out-
ward (away from the engine) slightly until the origi-
nal camber angle is obtained using special tool 8876
to move the upper control arm for proper adjustment.
(Fig. 3)
CAMBER
Move both pivot bolts of the upper control arm
together in or out. This will change the camber angle
significantly and little effect on the caster angle
using special tool 8876 to move the upper control
arm for proper adjustment. (Fig. 3)
After adjustment is made tighten the upper control
arm nuts to proper torque specification.
TOE ADJUSTMENT
The wheel toe position adjustment is the final
adjustment.
(1) Start the engine and turn wheels both ways
before straightening the wheels. Secure the steering
wheel with the front wheels in the straight-ahead
position.
(2) Loosen the tie rod jam nuts.
NOTE: Each front wheel should be adjusted for
one-half of the total toe position specification. This
will ensure the steering wheel will be centered
when the wheels are positioned straight-ahead.
(3) Adjust the wheel toe position by turning the
inner tie rod as necessary (Fig. 4).
(4) Tighten the tie rod jam nut to 75 N´m (55 ft.
lbs.).
(5) Verify the specifications
(6) Turn off engine.
STANDARD PROCEDURE - ALIGNMENT
LINK/COIL SUSPENSION
Before each alignment reading the vehicle should
be jounced (rear first, then front). Grasp each
bumper at the center and jounce the vehicle up and
down several times. Always release the bumper inthe down position.Set the front end alignment to
specifications while the vehicle is in its NOR-
MALLY LOADED CONDITION.
CAMBER:The wheel camber angle is preset and
is not adjustable.
CASTER:Check the caster of the front axle for
correct angle. Be sure the axle is not bent or twisted.
Road test the vehicle and make left and right turn.
Observe the steering wheel return-to-center position.
Low caster will cause poor steering wheel returnabil-
ity.
Caster can be adjusted by rotating the cams on the
lower suspension arm (Fig. 5).
TOE POSITION:The wheel toe position adjust-
ment should be the final adjustment.
Fig. 4 TIE ROD END
1 - JAM NUT
2 - TIE ROD - INNER
3 - TIE ROD END - OUTER
Fig. 5 ALIGNMENT ADJUSTMENT CAM
1 - BRACKET REINFORCEMENT
2 - ADJUSTING BOLT
3 - ADJUSTMENT CAM
DRWHEEL ALIGNMENT 2 - 5
WHEEL ALIGNMENT (Continued)

(1) Start the engine and turn wheels both ways
before straightening the wheels. Center and Secure
the steering wheel and turn off engine.
(2) Loosen the adjustment sleeve clamp bolts.
(3) Adjust the right wheel toe position with the
drag link. Turn the sleeve until the right wheel is at
the correct TOE-IN position. Position clamp bolts to
their original position and tighten to specifications.
Make sure the toe setting does not change dur-
ing clamp tightening.
(4) Adjust left wheel toe position with tie rod at
left knuckle. Turn the sleeve until the left wheel is at
the correct TOE-IN position. Position clamp bolts to
their original position and tighten to specifications.
Make sure the toe setting does not change dur-
ing clamp tightening.
(5) Verify the right toe setting and a straight steer-
ing wheel.
(6) Road test the vehicle.
SPECIFICATIONS
ALIGNMENT
NOTE: All alignment specifications are in degrees.
SPECIFICATIONS
DESCRIP-
TIONSPECIFICATION
VEHICLE
1500WHEEL
BASECASTER
(3.0É
Max,
+.75É
Target)CAMBER
(  .50É)TOTAL
TOE-IN
(  .10É)
4X2 120.5
in4.0É .0É .10É
4X2 140.5
in4.2É .0É .10É
4X2 160.5
in4.4É .0É .10É
VEHICLE
1500WHEEL
BASECASTER
(3.0É
Max,
+.75É
Target)CAMBER
( .50É)TOTAL
TOE-IN
( .10É)
4X4 120.5
in4.2É .0É .10É
4X4 140.5
in4.4É .0É .10É
4X4 160.5
in4.6É .0É .10É
DESCRIP-
TIONSPECIFICATION
MAX RT/LT
DIF-
FERENCE
4X2
1500Ð .40É .50É 0.06É
MAX RT/LT
DIF-
FERENCE
4X4
1500Ð .40É .60É 0.06É
VEHICLE
4X2
2500 &
3500WHEEL
BASECASTER
(3.25É
Max,
+.75É
Target)CAMBER
( .50É)TOTAL
TOE-IN
(0.20É
 .10É)
4X2
2500&3500140 4.0É 0.0É .10É  
.05É
4X2
2500&3500160 4.3É 0.0É .10É  
.05É
MAX RT/LT
DIF-
FERENCE
4X2
2500&3500Ð  0.4É  0.6É 0.1É
VEHICLE
4X4
2500&3500WHEEL
BASECASTER
(4.0É
Min,
+.75É
Target)CAMBER
(.25É
 .5É)TOTAL
TOE-IN
(0.20É
 .10É)
4X4
2500&3500140 4.5É .25É .10É  
.05É
4X4
2500&3500160 4.7É .25É .10É  
.05É
MAX RT/LT
DIF-
FERENCE
4X4
2500&3500Ð  .5É  .5É 0.1É
DESCRIP-
TIONREAR SPECIFICATION
CAMBER
(-.10É   0.35É)TOTAL TOE-IN
(0.30É   0.35É)
THRUST ANGLE 0É   0.4É
4X2
4X4
1500
THRUST ANGLE -0.2É   0.2É
4X2
4X4
2500&3500
2 - 6 WHEEL ALIGNMENTDR
WHEEL ALIGNMENT (Continued)

LOWER SUSPENSION ARM
REMOVAL
(1) Raise and support the vehicle.
(2) Paint or scribe alignment marks on the cam
adjusters and suspension arm for installation refer-
ence (Fig. 17).
(3) Remove the lower suspension arm nut, cam
and cam bolt from the axle.
(4) Remove the nut and bolt from the frame rail
bracket and remove the lower suspension arm (Fig.
17).
INSTALLATION
(1) Position the lower suspension arm at the axle
bracket and frame rail bracket.
(2) Install the rear bolt and finger tighten the nut.
(3) Install the cam bolt, cam and nut in the axle
and align the reference marks.
(4) Remove support and lower the vehicle.
(5) Tighten cam nut at the axle bracket to 217
N´m (160 ft. lbs.). Tighten rear nut at the frame
bracket to 217 N´m (160 ft. lbs.).
SHOCK
DIAGNOSIS AND TESTING - SHOCK
A knocking or rattling noise from a shock absorber
may be caused by movement between mounting
bushings and metal brackets or attaching compo-
nents. These noises can usually be stopped by tight-
ening the attaching nuts. If the noise persists,
inspect for damaged and worn bushings, and attach-
ing components. Repair as necessary if any of these
conditions exist.
A squeaking noise from the shock absorber may be
caused by the hydraulic valving and may be intermit-
tent. This condition is not repairable and the shock
absorber must be replaced.
The shock absorbers are not refillable or adjust-
able. If a malfunction occurs, the shock absorber
must be replaced. To test a shock absorber, hold it in
an upright position and force the piston in and out of
the cylinder four or five times. The action throughout
each stroke should be smooth and even.
The shock absorber bushings do not require any
type of lubrication. Do not attempt to stop bushing
noise by lubricating them. Grease and mineral oil-
base lubricants will deteriorate the bushing.
REMOVAL
(1) Remove the nut, retainer and grommet from
the upper stud in the engine compartment.
(2) Remove three nuts from the upper shock
bracket (Fig. 18).
(3) Remove the lower bolt from the axle bracket
(Fig. 19). Remove the shock absorber from engine
compartment.
INSTALLATION
(1) Position the lower retainer and grommet on the
upper stud. Insert the shock absorber through the
spring from engine compartment.
(2) Install the lower bolt and tighten to 135 N´m
(100 ft. lbs.).
(3) Install the upper shock bracket and three nuts.
Tighten nuts to 75 N´m (55 ft. lbs.).
(4) Install upper grommet and retainer. Install
upper shock nut and tighten to 47 N´m (35 ft. lbs).
Fig. 17 Adjustment Cam
1 - ADJUSTMENT CAM
2 - AXLE BRACKET
3 - BRACKET REINFORCEMENT
4 - LOWER SUSPENSION ARM
DRFRONT - LINK/COIL 2 - 35

DIFFERENTIAL & DRIVELINE
TABLE OF CONTENTS
page page
PROPELLER SHAFT......................1
HALF SHAFT...........................11
FRONT AXLE - C205F....................18
FRONT AXLE - 9 1/4 AA...................45REAR AXLE-91/4.......................69
REAR AXLE - 10 1/2 AA..................100
REAR AXLE - 11 1/2 AA..................127
PROPELLER SHAFT
TABLE OF CONTENTS
page page
PROPELLER SHAFT
DIAGNOSIS AND TESTING................1
STANDARD PROCEDURE.................3
SPECIFICATIONS........................6
SPECIAL TOOLS........................6
FRONT PROPELLER SHAFT
REMOVAL.............................6
INSTALLATION..........................7
REAR PROPELLER SHAFT
REMOVAL.............................7INSTALLATION..........................8
CENTER BEARING
REMOVAL.............................8
INSTALLATION..........................8
ADJUSTMENTS.........................8
SINGLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY..........................9
ASSEMBLY.............................9
PROPELLER SHAFT
DIAGNOSIS AND TESTING
PROPELLER SHAFT VIBRATION
Tires that are out-of-round or wheels that are
unbalanced, will cause a low frequency vibration.
Brake drums that are unbalanced will cause a
harsh, low frequency vibration.Driveline vibration can also result from loose or
damaged engine mounts.
Propeller shaft vibration increases as the vehicle
speed is increased. A vibration that occurs within a
specific speed range is not usually caused by a pro-
peller shaft being unbalanced. Defective universal
joints or an incorrect propeller shaft angle are usu-
ally the cause of such a vibration.
DRDIFFERENTIAL & DRIVELINE 3 - 1

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.
PROPELLER SHAFT 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 pro-
peller shaft is bent, it must be replaced.
(4) Inspect the universal joints to ensure that they
are not worn, are properly installed, and are cor-
rectly 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 SHAFTDR
PROPELLER SHAFT (Continued)

INSTALLATION
(1) Slide the slip yoke onto the transmission/trans-
fer case output shaft.
(2) Align and install center bearing on crossmem-
ber, if necessary and tighten nutts to 54 N´m (40 ft.
lbs.).
(3) Align reference marks on the propeller shaft
yoke and pinion companion flange (Fig. 13).
(4) Tighten pinion companion flange bolts to 115
N´m (85 ft. lbs.).
(5) Lower the vehicle.
CENTER BEARING
REMOVAL
(1) Remove rear propeller shaft.
(2) Mark the two shafts (Fig. 14) for installation
reference.
(3) Remove slip joint boot clamp and separate the
two shafts.
(4) Use hammer and punch to tap slinger away
from shaft to provide room for bearing splitter.
(5) Position Bearing Splitter Tool 1130 between
slinger and shaft.
CAUTION: Do not damage shaft spline during
removal of center bearing.
(6) Set shaft in press and press bearing off the
shaft.
INSTALLATION
NOTE: Two types of center bearings are used and
are not interchangeable. Install the same type as
the vehicle was built with.
(1) Install new slinger on shaft and drive into posi-
tion with appropriate installer tool.
(2) Install new center bearing on shaft with Bear-
ing Installer Tool 6052. Drive on shaft with hammer
until bearing is seated.
(3) Clean shaft splines and apply a coat of multi-
purpose grease.
(4) Align master splines and slide front and rear
half-shafts together. Reposition slip yoke boot and
install new clamp.
(5) Install propeller shaft in vehicle.
ADJUSTMENTS
CENTER BEARING
Launch shudder is a vibration that occurs at first
acceleration from a stop. Shudder vibration usually
peaks at the engines highest torque output. Shudder
is a symptom associated with vehicles using a two-
piece propeller shaft. To decrease shudder, lower the
center bearing in 1/8 inch increments. Use shim
stock or fabricated plates. Plate stock must be used
to maintain compression of the rubber insulator
around the bearing. Do not use washers. Replace the
original bolts with the appropriate increased length
bolts.
Fig. 13 REAR PROPELLER SHAFT
1 - COMPANION FLANGE
2 - PROPELLER SHAFT
Fig. 14 REFERENCE MARKS
1 - REFERENCE MARK
2 - CENTER BEARING
3 - BOOT CLAMP
4 - DUST BOOT
3 - 8 PROPELLER SHAFTDR
REAR PROPELLER SHAFT (Continued)

FRONT AXLE - C205F
TABLE OF CONTENTS
page page
FRONT AXLE - C205F
DESCRIPTION.........................18
OPERATION...........................18
DIAGNOSIS AND TESTING................18
REMOVAL.............................21
INSTALLATION.........................21
ADJUSTMENTS........................21
SPECIFICATIONS.......................29
SPECIAL TOOLS.......................30
AXLE SHAFTS
REMOVAL.............................33
INSTALLATION.........................33
AXLE SHAFT SEALS
REMOVAL.............................33
INSTALLATION.........................33
AXLE BEARINGS
REMOVAL.............................33INSTALLATION.........................34
PINION SEAL
REMOVAL.............................34
INSTALLATION.........................35
DIFFERENTIAL
DESCRIPTION.........................36
OPERATION...........................36
REMOVAL.............................36
DISASSEMBLY.........................37
ASSEMBLY............................38
INSTALLATION.........................38
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................39
INSTALLATION.........................39
PINION GEAR/RING GEAR
REMOVAL.............................40
INSTALLATION.........................42
FRONT AXLE - C205F
DESCRIPTION
The axle consists of an alumunum center section
with an axle tube extending from one side. The tube
is pressed into the differential housing. The power is
transferred from the axle through two constant veloc-
ity (C/V) drive shafts to the wheel hubs. The drive
shafts are identical and interchangeable.
OPERATION
The axle receives power from the propeller shaft.
The propeller shaft is connected to the pinion gear
which rotates the differential through the gear mesh
with the ring gear bolted to the differential case. The
engine power is transmitted to the axle shafts
through the pinion mate and side gears. The side
gears are splined to the axle shafts.
DIAGNOSIS AND TESTING
GEAR NOISE
Axle gear noise can be caused by insufficient lubri-
cant, incorrect backlash, tooth contact, worn/damaged
gears or the carrier housing not having the proper
offset and squareness.
Gear noise usually happens at a specific speed
range. The noise can also occur during a specific type
of driving condition. These conditions are accelera-
tion, deceleration, coast, or constant load.When road testing, first warm-up the axle fluid by
driving the vehicle at least 5 miles and then acceler-
ate the vehicle to the speed range where the noise is
the greatest. Shift out-of-gear and coast through the
peak-noise range. If the noise stops or changes
greatly:
²Check for insufficient lubricant.
²Incorrect ring gear backlash.
²Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. They usually do not cause
noise during straight-ahead driving when the gears
are unloaded. The side gears are loaded during vehi-
cle turns. A worn pinion mate shaft can also cause a
snapping 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-
3 - 18 FRONT AXLE - C205FDR

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:
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.
DRFRONT AXLE - C205F 3 - 19
FRONT AXLE - C205F (Continued)

FRONT AXLE - 9 1/4 AA
TABLE OF CONTENTS
page page
FRONT AXLE - 9 1/4 AA
DESCRIPTION.........................45
OPERATION...........................45
DIAGNOSIS AND TESTING................45
REMOVAL.............................48
INSTALLATION.........................48
ADJUSTMENTS........................49
SPECIFICATIONS.......................53
SPECIAL TOOLS.......................53
AXLE SHAFTS
REMOVAL.............................56
DISASSEMBLY.........................56
ASSEMBLY............................58
INSTALLATION.........................58
AXLE SHAFT SEALS
REMOVAL.............................58
INSTALLATION.........................58PINION SEAL
REMOVAL.............................60
INSTALLATION.........................60
DIFFERENTIAL
DESCRIPTION.........................61
OPERATION...........................61
REMOVAL.............................61
DISASSEMBLY.........................62
ASSEMBLY............................63
INSTALLATION.........................63
DIFFERENTIAL CASE BEARINGS
REMOVAL.............................64
INSTALLATION.........................65
PINION GEAR/RING GEAR
REMOVAL.............................65
INSTALLATION.........................66
FRONT AXLE - 9 1/4 AA
DESCRIPTION
The axle consists of a cast iron center casting dif-
ferential housing with axle shaft tubes extending
from each side. The tubes are pressed into the differ-
ential housing and welded. The design has the cen-
terline of the pinion set above the centerline of the
ring gear. The axle has full-floating axle shafts,
meaning the shaft are supported by the hub bear-
ings. The axle has a vent used to relieve internal
pressure caused by lubricant vaporization and inter-
nal expansion.
OPERATION
The axle receives power from the front propeller
shaft. The propeller shaft is connected to the pinion
gear which rotates the differential through the gear
mesh with the ring gear bolted to the differential
case. The engine power is transmitted to the axle
shafts through the pinion mate and side gears. The
side gears are splined to the axle shafts.
DIAGNOSIS AND TESTING
GEAR NOISE
Axle gear noise can be caused by insufficient lubri-
cant, incorrect backlash, tooth contact, worn/damaged
gears or the carrier housing not having the proper
offset and squareness.Gear noise usually happens at a specific speed
range. The noise can also occur during a specific type
of driving condition. These conditions are accelera-
tion, deceleration, coast, or constant load.
When road testing, first warm-up the axle fluid by
driving the vehicle at least 5 miles and then acceler-
ate the vehicle to the speed range where the noise is
the greatest. Shift out-of-gear and coast through the
peak-noise range. If the noise stops or changes
greatly:
²Check for insufficient lubricant.
²Incorrect ring gear backlash.
²Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. They usually do not cause
noise during straight-ahead driving when the gears
are unloaded. The side gears are loaded during vehi-
cle turns. A worn pinion mate shaft can also cause a
snapping 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
DRFRONT AXLE - 9 1/4 AA 3 - 45

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 front/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 vibration. Do
not overlook engine accessories, brackets and drive
belts.
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 - 46 FRONT AXLE - 9 1/4 AADR
FRONT AXLE - 9 1/4 AA (Continued)