2003 DODGE RAM Front differential

(17) Installnewring gear bolts and alternately
tighten to 108 N´m (80 ft. lbs.) (Fig. 61).
CAUTION: Never reuse the ring gear bolts. The
bolts can fracture causing extensive damage.
(18) Install differential in housing and verify gear
mesh, backlash and contact pattern.
(19) Install differential cover and fill with gear
lubricant.
Fig. 59 PINION NUT
1 - DIFFERENTIAL HOUSING
2 - COMPANION FLANGE HOLDER
3 - TORQUE WRENCH
Fig. 60 PINION ROTATING TORQUE
1 - PINION COMPANION FLANGE
2 - TORQUE WRENCH
Fig. 61 RING GEAR BOLTS
1 - TORQUE WRENCH
2 - BOLTS
3 - RING GEAR
4 - DIFFERENTIAL CASE
3 - 44 FRONT AXLE - C205FDR
PINION GEAR/RING GEAR (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)

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.
DRFRONT AXLE - 9 1/4 AA 3 - 47
FRONT AXLE - 9 1/4 AA (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) Remove wheels and tires.
(2) Remove brake calipers and rotors.
(3) Disconnect ABS wheel speed sensors.
(4) Disconnect axle vent hose.
(5) Remove front propeller shaft.
(6) Disconnect stabilizer bar links at the axle
brackets.
(7) Disconnect shock absorbers from axle brackets.
(8) Disconnect track bar from the axle bracket.
(9) Disconnect tie rod and drag link from the steer-
ing knuckles.
(10) Position suitable lifting device under the axle
assembly.
(11) Secure axle to lifting device.
(12) Mark suspension alignment cams for installa-
tion reference.
(13) Disconnect upper and lower suspension arms
from the axle bracket.(14) Lower the axle. The coil springs will drop
with the axle.
(15) 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.
(2) Secure axle to lifting device.
(3) Position the axle under the vehicle.
(4) Install springs, retainer clip and bolts.
(5) Raise axle and align it with the spring pads.
3 - 48 FRONT AXLE - 9 1/4 AADR
FRONT AXLE - 9 1/4 AA (Continued)

(6) Position upper and lower suspension arms in
the axle brackets. Install bolts, nuts and align the
suspension alignment cams to the reference marks.
Do not tighten at this time.
(7) Connect track bar to the axle bracket and
install the bolt. Do not tighten at this time.
(8) Install shock absorber and tighten bolts to 121
N´m (89 ft. lbs.).
(9) Install stabilizer bar link to the axle bracket.
Tighten the nut to 68 N´m (50 ft. lbs.).
(10) Install drag link and tie rod to the steering
knuckles and tighten the nuts to 108 N´m (80 ft.
lbs.).
(11) Install ABS wheel speed sensors.
(12) Install rotors and brake calipers.
(13) Connect the axle vent hose.
(14) Install front propeller shaft.
(15) Check and add differential lubricant, if neces-
sary.
(16) Install wheel and tire assemblies.
(17) Remove lower the vehicle.
(18) Tighten upper suspension arm nuts at axle to
149 N´m (110 ft. lbs.). Tighten upper suspension arm
nuts at frame to 149 N´m (110 ft. lbs.).
(19) Tighten lower suspension arm nuts at axle to
190 N´m (140 ft. lbs.). Tighten the lower suspension
arm nuts at frame to 190 N´m (140 ft. lbs.).
(20) Tighten track bar bolt at the axle bracket to
176 N´m (130 ft. lbs.).
(21) Check front wheel alignment.
ADJUSTMENTS
Ring and pinion gears are supplied as matched
sets only. Compensation for pinion depth variance is
achieved with a select shim. The shim is located
between the rear pinion bearing and the pinion gear
head.
PINION DEPTH MEASUREMENT AND ADJUSTMENT
Measurements are taken with pinion bearing cups
and pinion bearings installed in the housing. Take
measurements with Pinion Gauge Set and Dial Indi-
cator C-3339 (Fig. 1).
(1) Assemble Pinion Height Block 6739, Pinion
Block 8878 and rear pinion bearing onto Screw 6741
(Fig. 1).
(2) Insert assembled height gauge components,
rear bearing and screw into the housing through pin-
ion bearing cups (Fig. 2).
(3) Install front pinion bearing and install the
Cone-nut 6740 hand tight. Then check tool rotating
torque with an inch pound torque wrench. The rotat-
ing torque should be 1.7-2.26 N´m (15-20 in. lbs.)
(4) Place Arbor Disc 8289 on Arbor D-115-3 in posi-
tion in the housing side bearing cradles (Fig. 3).(5) Install differential bearing caps on arbor discs
and snug the bearing cap bolts. Then cross tighten
cap bolts to 85 N´m (63 ft. lbs.).
Fig. 1 PINION GEAR DEPTH GAUGE TOOLS
1 - DIAL INDICATOR
2 - ARBOR
3 - PINION HEIGHT BLOCK
4 - CONE
5 - SCREW
6 - PINION BLOCK
7 - SCOOTER BLOCK
8 - ARBOR DISC
Fig. 2 PINION HEIGHT BLOCK
1. PINION HEIGHT BLOCK
2. PINION BLOCK
DRFRONT AXLE - 9 1/4 AA 3 - 49
FRONT AXLE - 9 1/4 AA (Continued)

NOTE: Arbor should rotate freely in the arbor disc.
(6) Assemble Dial Indicator C-3339 into Scooter
Block D-115-2 and secure set screw.
(7) Position Scooter Block/Dial Indicator flush on
the pinion height block. Hold scooter block and zero
the dial indicator.
(8) Slowly slide the scooter block across the pinion
height block over to the arbor (Fig. 4). Move the
scooter block till dial indicator crests the arbor, then
record the highest reading.
(9) Select a shim equal to the dial indicator read-
ing.
(10) Install the select shim between the rear pin-
ion bearing and the pinion gear head.
DIFFERENTIAL CASE BEARING PRELOAD AND
GEAR BACKLASH
Backlash is adjusted by moving the adjusters in
and out or both. By moving the adjusters the case/
ring gear will move closer or further away from the
pinion. In most cases this adjustment can be used to
achieve the correct gear tooth pattern and set the
case bearing preload.
(1) Remove adjuster lock bolts and adjuster locks
(Fig. 5).
(2) Loosen the differential bearing caps.
(3) Slide differential case toward the pinion gear
until the gears make contact/zero backlash. If zero
backlash cannot be obtained, turn the pinion side
adjuster until zero backlash is obtained.
(4) Holding the differential case toward the pinion
gear, turn bearing adjusters with Spanner Wrench8883 until they make contact with the differential
bearings/cups.
(5) Back off the ring gear side adjuster 4 holes, to
obtain initial ring gear backlash.
Fig. 3 GAUGE TOOLS IN HOUSING
1. PINION HEIGHT BLOCK
2. PINION BLOCK
3. ARBOR
4. ARBOR DISCS
Fig. 4 PINION DEPTH MEASUREMENT
1. DIAL INDICATOR
2. ARBOR
3. SCOOTER BLOCK
Fig. 5 ADJUSTER LOCK BOLT
1 - DIFFERENTIAL CASE
2 - ADJUSTER LOCK
3 - ADJUSTER LOCK BOLT
4 - BEARING CAP BOLT
3 - 50 FRONT AXLE - 9 1/4 AADR
FRONT AXLE - 9 1/4 AA (Continued)

(6) Install ring gear side adjuster lock and bolt. Do
not tighten adjuster lock bolt at this time.
(7) Tighten pinion gear side adjuster firmly
against the differential case bearing cup.
(8) Rotate the pinion several times to seat the dif-
ferential bearings.
(9) Loosen pinion gear side adjuster until it is no
longer in contact with the bearing cup, then tighten
it until it makes contact.
(10) Tighten pinion gear side adjuster an addi-
tional:
²New Bearings:6 Adjuster Holes
²Original Bearings:4 Adjuster Holes
(11) Install pinion gear side adjuster lock and bolt.
Do not tighten adjuster lock bolt at this time.
(12) Tighten bearing cap bolts to 85 N´m (63 ft.
lbs.).
(13) Tighten adjuster lock bolts to 25 N´m (18 ft.
lbs.).
(14) Measure ring gear backlash with a Dial Indi-
cator C-3339 and Dial Indicator Stud L-4438 at eight
points around the drive side of the ring gear (Fig. 6).
The backlash should be 0.08-0.25 mm (0.003-0.010
in) with a preferred backlash of 0.13-0.18 mm (0.005-
0.007 in).
NOTE: Backlash measurement should not vary
more than 0.05 mm (0.002 in) between measuring
points. If measurement does vary inspect the gears
for burrs, the differential case flange and ring gear
mounting.GEAR TOOTH CONTACT PATTERN
Gear tooth contact pattern is used to verify the cor-
rect running position of the ring and pinion gears.
This will produce low noise and long gear life. Gears
which are not positioned properly may be noisy and
have shortened gear life.
(1) Wipe clean each tooth of the ring gear.
(2) Apply gear marking compound to all of the ring
gear teeth.
(3) Verify bearing cap bolts are torque to specifica-
tion.
(4) Apply the brakes lightly to create a 14 N´m (10
ft. lbs.) pinion rotating torque.
(5) Rotate the pinion/pinion yoke 4 full revolutions
in each directions.
(6) Read gear tooth contact pattern:
²Gear contact pattern is correct (Fig. 7). Backlash
and pinion depth is correct.
²Ring gear too far away from pinion gear (Fig. 8).
Decrease backlash, by moving the ring closer to the
pinion gear using the adjusters.
Fig. 6 RING GEAR BACKLASH
1 - DIAL INDICATOR
2 - RING GEAR
Fig. 7 CORRECT CONTACT PATTERN
Fig. 8 INCORRECT BACKLASH
1 - COAST SIDE TOE
2 - DRIVE SIDE HEEL
DRFRONT AXLE - 9 1/4 AA 3 - 51
FRONT AXLE - 9 1/4 AA (Continued)