1998 DODGE RAM 1500 4 wheel drive

DIFFERENTIAL & DRIVELINE
TABLE OF CONTENTS
page page
PROPELLER SHAFT......................1
HALF SHAFT...........................20
FRONT AXLE - C205F....................27
FRONT AXLE - 9 1/4 AA...................54REAR AXLE-91/4.......................80
REAR AXLE - 10 1/2 AA..................112
REAR AXLE - 11 1/2 AA..................140
PROPELLER SHAFT
TABLE OF CONTENTS
page page
PROPELLER SHAFT
DIAGNOSIS AND TESTING................1
STANDARD PROCEDURE.................3
SPECIFICATIONS........................6
SPECIAL TOOLS........................6
PROPELLER SHAFT- LD FRONT
REMOVAL.............................6
INSTALLATION..........................7
PROPELLER SHAFT - HD FRONT
REMOVAL.............................7
INSTALLATION..........................7
REAR PROPELLER SHAFT
REMOVAL.............................8
INSTALLATION..........................8CENTER BEARING
REMOVAL.............................9
INSTALLATION..........................9
ADJUSTMENTS.........................9
SINGLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY
DISASSEMBLY - WITH SNAP RINGS......10
DISASSEMBLY - WITH INJECTED RINGS . . . 11
ASSEMBLY
ASSEMBLY - WITH SNAP RINGS.........12
ASSEMBLY - WITH INJECTED RINGS......13
DOUBLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY.........................16
ASSEMBLY............................17
PROPELLER SHAFT
DIAGNOSIS AND TESTING
PROPELLER SHAFT VIBRATION
Out-of-round tires or wheels that are out of bal-
ance, will cause a low frequency vibration.
Driveline vibration can also caused by loose or
damaged engine mounts.Propeller shaft vibration increases with vehicle
speed. A vibration that occurs at a specific speed
range, is not usually caused by an out of balance pro-
peller shaft. Defective universal joints or an incorrect
propeller shaft angle are usually 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
If propeller shaft is suspected of being out of bal-
ance, use the following procedure.
NOTE: Indexing propeller shaft 180É relative to the
yoke may eliminate some vibrations.
(1) Raise and support vehicle.
(2) Clean all foreign material from the propeller
shaft and universal joints.
(3) Inspect propeller shaft for missing balance
weights, broken welds and bent areas.If propeller
shaft is bent, it must be replaced.
(4) Inspect universal joints for wear and properly
installed.
(5) Check propeller shaft bolt torques.
(6) Remove wheels and install lug nuts to retain
brake rotors.
(7) Mark and number the shaft six inches from the
pinion yoke end at four positions 90É apart.
(8) Run and accelerate 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).
Fig. 1 CLAMP SCREW AT POSITION 1
1 - CLAMP
2 - SCREWDRIVER
3 - 2 PROPELLER SHAFTDR
PROPELLER SHAFT (Continued)

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.
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/CV joint.
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 and lis-
ten 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.
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.
3 - 28 FRONT AXLE - C205FDR
FRONT AXLE - C205F (Continued)

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 and lis-
ten 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.
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.
DRFRONT AXLE - 9 1/4 AA 3 - 55
FRONT AXLE - 9 1/4 AA (Continued)

ASSEMBLY
(1) Pack the bearing caps 1/3 full of wheel bearing
lubricant. Apply extreme pressure (EP), lithium-base
lubricant to aid in installation.
(2) Position the spider in the yoke. Insert the seals
and bearings. Tap the bearing caps into the yoke
bores far enough to hold the spider in position.
(3) Place the socket (driver) against one bearing
cap. Position the yoke with the socket in a vise.
(4) Tighten the vise to force the bearing caps into
the yoke. Force the caps enough to install the retain-
ing clips.
(5) Install the bearing cap retaining clips.
(6) Install axle shaft.
INSTALLATION
(1) Clean axle shaft and apply a thin film of
Mopar Wheel Bearing Grease to the shaft splines
and hub bore.
(2) Install axle shaft through the steering knuckle
and into the differential side gears (Fig. 24).
(3) Install hub bearing in the knuckle.
(4) Install hub bearing bolts and tighten to 202
N´m (149 ft. lbs.).
(5) Install ABS wheel speed sensor, brake rotor
and caliper.
(6) Install axle washer and nut. Tighten axle nut
to 179 N´m (132 ft. lbs.).
(7) Rotate axle several 5 to 10 times to seat the
wheel bearing.
(8) Tighten axle nut to final torque of 356 N´m
(263 ft. lbs.).
(9) Align nut to next cotter pin hole and install
new cotter pin.
AXLE SHAFT SEALS
REMOVAL
(1) Remove hub bearings and axle shafts.
(2) Remove differential from differential housing.
(3) Remove differential bearing adjusters (Fig. 25).
(4) Remove axle seals (Fig. 26) located behind
adjusters with Receiver 8498 and Extractor 6310.
(5) Install Receiver 8498 into the adjuster bore.
Fig. 24 AXLE SHAFT
1 - AXLE YOKE
2 - AXLE SHAFT
3 - KNUCKLE
Fig. 25 ADJUSTERS
1 - DIFFERENTIAL CASE BEARING ADJUSTERS
2 - DIFFERENTIAL HOUSING
Fig. 26 AXLE SHAFT SEAL
1 - ADJUSTER THREADS
2 - SEAL
DRFRONT AXLE - 9 1/4 AA 3 - 69
AXLE SHAFTS (Continued)

LOW SPEED KNOCK
Low speed knock is generally caused by:
²Worn U-joint.
²Worn side gear thrust washers.
²Worn pinion shaft bore.
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.
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.
DRREAR AXLE - 9 1/4 3 - 81
REAR AXLE - 9 1/4 (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. 40).
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. Add a container of Mopar Limited Slip
Additive after repair service 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.
Fig. 38 BEARING CAPS
1 - REFERENCE MARKS
2 - REFERENCE MARKS
3 - ADJUSTER LOCK
4 - BEARING CAP
Fig. 39 COVER SEALANT
1 - SEALANT
2 - DIFFERENTIAL COVER
3 - 100 REAR AXLE-91/4DR
DIFFERENTIAL (Continued)

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. 41).
(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 Holding Fixture 8136 in vise and set
differential case on fixture (Fig. 42).
(2) Remove pinion gear mate shaft screw.
(3) Remove pinion gear mate shaft.
Fig. 40 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
Fig. 41 ROTATING TORQUE TEST
1 - SPECIAL TOOL WITH BOLT IN CENTER HOLE
2 - TORQUE WRENCH
Fig. 42 DIFFERENTIAL CASE FIXTURE
1 - HOLDING FIXTURE
2 - VISE
3 - DIFFERENTIAL
DRREAR AXLE - 9 1/4 3 - 101
DIFFERENTIAL-TRAC-LOK (Continued)