service DODGE RAM 2003 Service Owner's Manual

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.
3 - 72 REAR AXLE-91/4DR
REAR AXLE - 9 1/4 (Continued)

sent thousands of an inch deviation from the stan-
dard. If the number is negative, add that value to the
required thickness of the depth shims. If the numberis positive, subtract that value from the thickness of
the depth shim. If the number is 0 no change is nec-
essary.
PINION GEAR DEPTH VARIANCE
Original Pinion
Gear Depth
VarianceReplacement Pinion Gear Depth Variance
24232221 0 +1 +2 +3 +4
+4+0.008 +0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 0
+3+0.007 +0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.001
+2+0.006 +0.005 +0.004 +0.003 +0.002 +0.001 020.00120.002
+1+0.005 +0.004 +0.003 +0.002 +0.001 020.00120.00220.003
0+0.004 +0.003 +0.002 +0.001 020.00120.00220.00320.004
21+0.003 +0.002 +0.001 020.00120.00220.00320.00420.005
22+0.002 +0.001 020.00120.00220.00320.00420.00520.006
23+0.001 020.00120.00220.00320.00420.00520.00620.007
24020.00120.00220.00320.00420.00520.00620.00720.008
PINION DEPTH MEASUREMENT
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. 4).
(1) Assemble Pinion Height Block 6739, Pinion
Block 8542 and rear pinion bearing onto Screw 6741
(Fig. 4).
(2) Insert assembled height gauge components,
rear bearing, and screw into the housing through
pinion bearing cups (Fig. 5).
(3) Install front pinion bearing and Cone-Nut 6740
hand tight (Fig. 4).
(4) Place Arbor Disc 8541 on Arbor D-115-3 in posi-
tion in the housing side bearing cradles (Fig. 6).
Install differential bearing caps on arbor discs and
tighten cap bolts to 41 N´m (30 ft. lbs.).
NOTE: Arbor Discs 8541 has different step diame-
ters to fit other axles. Choose proper step for axle
being serviced.
(5) Assemble Dial Indicator C-3339 into Scooter
Block D-115-2 and secure set screw.
(6) Place Scooter Block/Dial Indicator in position
in axle housing so dial probe and scooter block are
flush against the rearward surface of the pinion
height block (Fig. 4). Hold scooter block in place and
zero the dial indicator. Tighten dial indicator face
lock screw.
Fig. 4 PINION 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
DRREAR AXLE - 9 1/4 3 - 75
REAR AXLE - 9 1/4 (Continued)

CAUTION: Never loosen pinion nut to decrease pin-
ion bearing rotating torque and never exceed spec-
ified preload torque. If rotating torque is exceeded,
a new collapsible spacer must be installed.(10) If rotating torque is low, use Holder 6719 to
hold the companion flange and tighten pinion nut in
6.8 N´m (5 ft. lbs.) increments until proper rotating
torque is achieved.
NOTE: The bearing rotating torque should be con-
stant during a complete revolution of the pinion. If
the rotating torque varies, this indicates a binding
condition.
NOTE: The seal replacement is unacceptable if the
final pinion nut torque is less than 285 N´m (210 ft.
lbs.).
(11) Install propeller shaft with the installation
reference marks aligned.
(12) Tighten the companion flange bolts to 108
N´m (80 ft. lbs.).
(13) Install brake rotors.
(14) Check the differential lubricant level.
DIFFERENTIAL
DESCRIPTION
The differential case is a one-piece design. The dif-
ferential pinion mate shaft is retained with a
threaded pin. Differential bearing preload and ring
gear backlash are set and maintained by threaded
adjusters at the outside of the differential housing.
Pinion bearing preload is set and maintained by the
use of a collapsible spacer. The removable differential
cover provides a means for inspection and service.
OPERATION
During straight-ahead driving, the differential pin-
ion gears do not rotate on the pinion mate shaft. This
occurs because input torque applied to the gears is
divided and distributed equally between the two side
gears. As a result, the pinion gears revolve with the
pinion mate shaft but do not rotate around it (Fig.
28).
When turning corners, the outside wheel must
travel a greater distance than the inside wheel to
complete a turn. To accomplish this, the differential
allows the axle shafts to turn at unequal speeds (Fig.
29). In this instance, the input torque applied to the
pinion gears is not divided equally. The pinion gears
now rotate around the pinion mate shaft in opposite
directions. This allows the side gear and axle shaft
attached to the outside wheel to rotate at a faster
speed.
REMOVAL
(1) Remove filler plug from the differential cover.
Fig. 26 TIGHTENING PINION NUT
1 - DIFFERENTIAL HOUSING
2 - COMPANION FLANGE HOLDER
3 - TORQUE WRENCH
Fig. 27 PINION ROTATION TORQUE
1 - COMPANION FLANGE
2 - TORQUE WRENCH
3 - 86 REAR AXLE-91/4DR
PINION SEAL (Continued)

CAUTION: If cover is not installed within 3 to 5 min-
utes, the cover must be cleaned and new RTV
applied or adhesion quality will be compromised.
(8) Install the cover and any identification tag and
tighten cover bolts to 41 N´m (30 ft. lbs.).
(9) Fill differential with lubricant to bottom of the
fill plug hole. Refer to the Lubricant Specifications
for the correct quantity and type.
NOTE: Trac-lokŸ differential equipped vehicles
should be road tested by making 10 to 12 slow fig-
ure-eight turns. This maneuver will pump the lubri-
cant through the clutch discs to eliminate a
possible chatter noise complaint.
DIFFERENTIAL-TRAC-LOK
DESCRIPTION
The optional Trac-Loktdifferential case has a one-
piece design and the similar internal components as
a standard differential, plus two clutch disc pack-
s.The differential pinion mate shaft is retained with
a threaded pin. Differential bearing preload and ring
gear backlash are set and maintained by threaded
adjusters at the outside of the differential housing.
Pinion bearing preload is set and maintained by the
use of a collapsible spacer. The removable differential
cover provides a means for inspection and service.
OPERATION
This differential clutches are engaged by two con-
current forces. The first being the preload force
exerted through Belleville spring washers within the
clutch packs. The second is the separating forces gen-erated by the side gears as torque is applied through
the ring gear (Fig. 36).
This design provides the differential action needed
for turning corners and for driving straight ahead
during periods of unequal traction. When one wheel
looses traction, the clutch packs transfer additional
torque to the wheel having the most traction. This
differential resist wheel spin on bumpy roads and
provide more pulling power when one wheel looses
traction. Pulling power is provided continuously until
both wheels loose traction. If both wheels slip due to
unequal traction, Trac-loktoperation is normal. In
extreme cases of differences of traction, the wheel
with the least traction may spin.DIAGNOSIS AND TESTING
The most common problem is a chatter noise when
turning corners. Before removing the unit for repair,
drain, flush and refill the axle with the specified
lubricant. A container of Mopar Trac-loktLubricant
Fig. 35 COVER SEALANT
1 - SEALANT
2 - DIFFERENTIAL COVER
Fig. 36 TRAC-LOK LIMITED SLIP DIFFERENTIAL
1 - CASE
2 - RING GEAR
3 - DRIVE PINION
4 - PINION GEAR
5 - MATE SHAFT
6 - CLUTCH PACK
7 - SIDE GEAR
8 - CLUTCH PACK
DRREAR AXLE - 9 1/4 3 - 89
DIFFERENTIAL (Continued)

(friction modifier) should be added after repair ser-
vice or during a lubricant change.
After changing the lubricant, drive the vehicle and
make 10 to 12 slow, figure-eight turns. This maneu-
ver will pump lubricant through the clutches. This
will correct the condition in most instances. If the
chatter persists, clutch damage could have occurred.
DIFFERENTIAL TEST
The differential can be tested without removing the
differential case by measuring rotating torque. Make
sure brakes are not dragging during this measure-
ment.
(1) Place blocks in front and rear of both front
wheels.
(2) Raise one rear wheel until it is completely off
the ground.
(3) Engine off, transmission in neutral, and park-
ing brake off.
(4) Remove wheel and bolt Special Tool 6790 or
equivalent tool to studs.
(5) Use torque wrench on special tool to rotate
wheel and read rotating torque (Fig. 37).
(6) If rotating torque is less than 41 N´m (30 ft.
lbs.) or more than 271 N´m (200 ft. lbs.) on either
wheel the unit should be serviced.
DISASSEMBLY
(1) Clamp Fixture 6965 in a vise and position the
differential case on the fixture (Fig. 38).
(2) Remove ring gear if the ring gear is to be
replaced.
(3) Remove pinion gear mate shaft lock screw.
(4) Remove pinion gear mate shaft with a drift and
hammer.(5) Install and lubricate Step Plate C-6960-3 (Fig.
39).
(6) Assemble Threaded Adapter C-6960-1 into top
side gear. Thread Forcing Screw C-6960-4 into
adapter until it becomes centered in adapter plate.
Fig. 37 ROTATING TORQUE TEST
1 - SPECIAL TOOL WITH BOLT IN CENTER HOLE
2 - TORQUE WRENCH
Fig. 38 DIFFERENTIAL CASE FIXTURE
1 - HOLDING FIXTURE
2 - VISE
3 - DIFFERENTIAL
Fig. 39 STEP PLATE
1 - LOWER SIDE GEAR
2 - DIFFERENTIAL CASE
3 - DISC
3 - 90 REAR AXLE-91/4DR
DIFFERENTIAL-TRAC-LOK (Continued)

INSTALLATION
(1) Install differential side bearings with Installer
C-4213 and Handle C-4171 (Fig. 49).
(2) Install differential case into housing.
PINION GEAR/RING GEAR/
TONE RING
REMOVAL
NOTE: The ring gear and pinion are serviced in a
matched set. Never replace one gear without replac-
ing the other matching gear.
(1) Mark companion flange and propeller shaft for
installation reference.
(2) Disconnect propeller shaft from the companion
flange and tie propeller shaft to underbody.
(3) Remove axle shafts.
(4) Remove differential from the differential hous-
ing.
(5) Place differential case in a vise with soft metal
jaw protectors..
(6) Remove ring gear bolts from the differential
case.
(7) Drive ring gear off the differential case with a
rawhide hammer (Fig. 50).(8) Install bolts into two of the threaded holes in
the companion flange 180É apart.
(9) Position Holder 6719 against the companion
flange and install a bolt and washer into one of the
remaining threaded holes. Tighten the bolts so the
Holder 6719 is held to the flange.
(10) Use Holder 6719 to hold companion flange
and remove the companion flange nut and washer.
(11) Remove companion flange with Remover
C-452 (Fig. 51).
(12) Remove pinion gear from the housing (Fig.
52).
Fig. 49 DIFFERENTIAL CASE BEARING
1 - HANDLE
2 - DIFFERENTIAL
3 - BEARING
4 - INSTALLER
Fig. 50 RING GEAR
1 - CASE
2 - RING GEAR
3 - RAWHIDE HAMMER
Fig. 51 COMPANION FLANGE
1 - COMPANION FLANGE
2 - REMOVER
3 - 94 REAR AXLE-91/4DR
DIFFERENTIAL CASE BEARINGS (Continued)

(18) Remove rear pinion bearing (Fig. 56) from the
pinion shaft with Puller C-293-PA and Adapters
C-293-37.
(19) Remove pinion depth shim (Fig. 57) from the
pinion shaft and record shim thickness.INSTALLATION
NOTE: The ring gear and pinion are serviced in a
matched set. Do not replace one gear without
replacing the other matching gear. If ring and pinion
gears or bearings are replaced, Refer to Adjust-
ments for Pinion Gear Depth Setting.
(1) Apply Mopar Door Ease or equivalent stick
lubricant to outside surface of the pinion bearing
cups.
(2) Install rear pinion bearing cup (Fig. 58) with
Installer C-4308 and Driver Handle C-4171 and ver-
ify cup is seated.
(3) Install front pinion bearing cup (Fig. 59) with
Installer D-129 and Handle C-4171 and verify cup is
seated.
(4) Lubricate and install front pinion bearing into
the housing.
(5) Apply a light coating of gear lubricant on the
lip of pinion seal. Install seal with Installer C-4076-B
and Handle C-4735-1 (Fig. 60).
Fig. 56 REAR PINION BEARING
1 - PULLER
2 - VISE
3 - ADAPTERS
4 - PINION SHAFT
Fig. 57 PINION DEPTH SHIM
1 - PINION DEPTH SHIM
2 - PINION GEAR
Fig. 58 REAR PINION BEARING CUP
1 - INSTALLER
2 - HANDLE
3 - 96 REAR AXLE-91/4DR
PINION GEAR/RING GEAR/TONE RING (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.
3 - 102 REAR AXLE - 10 1/2 AADR
REAR AXLE - 10 1/2 AA (Continued)

PINION GEAR/RING GEAR/
TONE RING
REMOVAL
NOTE: The ring and pinion gears are service in a
matched set. Never replace the ring gear/pinion
gear without replacing the other matching gear.
(1) Mark pinion flange and propeller shaft for
installation alignment.
(2) Disconnect propeller shaft from pinion flange
and remove propeller shaft.
(3) Remove differential from axle housing.
(4) Place differential on Plug 8888 and drive
exciter ring off the differential case with a hammer
and punch (Fig. 49).
NOTE: Do not remove the exciter ring if it is not
being replaced.
(5) Place differential case in a vise with soft metal
jaw protectors
(6) Remove bolts holding ring gear to differential
case.(7) Drive ring gear from differential case with a
soft hammer (Fig. 50).
(8) Hold pinion flange with Flange Wrench 8979
(Fig. 51) and remove pinion flnage nut and washer.
(9) Remove pinion flange from the pinion with Pin-
ion Flange Puller 8992 (Fig. 52).
(10) Remove pinion gear from housing, with Pinion
Driver 8977 (Fig. 53) and a hammer.
Fig. 49 EXCITER RING
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - PUNCH
4 - EXCITER RING
Fig. 50 RING GEAR
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - HAMMER
Fig. 51 FLANGE WRENCH
1 - PINION FLANGE
2 - FLANGE WRENCH
3 - 122 REAR AXLE - 10 1/2 AADR

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.
DRREAR AXLE - 11 1/2 AA 3 - 129
REAR AXLE - 11 1/2 AA (Continued)