1998 DODGE RAM 1500 check engine

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)

(4) Align hole in the pinion gears with hole in the
differential case.
(5) Install pinion shaft.
(6) Installnewpinion shaft lock bolt and tighten
to 52 N´m (38 ft. lbs.).
INSTALLATION
(1) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.
CAUTION: Do not use water, steam, kerosene or
gasoline for cleaning.
(2) Lubricate differential case bearing.
(3) Install differential case with bearings cups into
the housing.
(4) Install bearing caps and bolts (Fig. 41). Tighten
the bearing cap bolts finger-tight.
NOTE: Do not torque bearing cap and bolts at this
time.
(5) 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.
(6) Holding the differential case toward the pinion
gear, turn bearing adjusters with Spanner Wrench
8883 until they make contact with the differential
bearings/cups.(7) Back off the ring gear side adjuster 4 holes, to
obtain initial ring gear backlash.
(8) Install ring gear side adjuster lock and bolt. Do
not tighten adjuster lock bolt at this time.
(9) Tighten pinion gear side adjuster firmly
against the differential case bearing cup.
(10) Rotate the pinion several times to seat the dif-
ferential bearings.
(11) Loosen pinion gear side adjuster until it is no
longer in contact with the bearing cup.
(12) Tighten pinion gear side adjuster until it just
makes contact with the bearing cup.
(13) Tighten pinion gear side adjuster an addi-
tional:
²New Bearings:6 Adjuster Holes
²Original Bearings:4 Adjuster Holes
(14) Install pinion gear side adjuster lock and bolt.
Do not tighten adjuster lock bolt at this time.
(15) Tighten bearing cap bolts to 85 N´m (63 ft.
lbs.).
(16) Tighten adjuster lock bolts to 25 N´m (18 ft.
lbs.) (Fig. 42).
(17) Measure ring gear backlash and check gear
tooth contact pattern. Refer to Adjustments for pro-
cedure.
(18) Install axle shafts and hub bearings.
(19) Install differential housing gasket and cover.
Tighten cover bolts to 40 N´m (30 ft. lbs.).
Fig. 41 CASE BEARING CAP
1 - DIFFERENTIAL HOUSING
2 - BEARING CAP
3 - ADJUSTERFig. 42 ADJUSTER LOCK BOLT
1 - DIFFERENTIAL CASE
2 - ADJUSTER LOCK
3 - ADJUSTER LOCK BOLT
4 - BEARING CAP BOLT
3 - 74 FRONT AXLE - 9 1/4 AADR
DIFFERENTIAL (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)

(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 COVER
REMOVAL
(1) With vehicle in neutral, position vehicle on
hoist.
(2) Remove drain plug.
(3) Remove cover bolts.
(4) Remove cover and drain lubricant.
INSTALLATION
(1) Apply a 6.35mm (1/4 in.) bead of Mopar Sili-
cone Rubber Sealant or equivalent to the housing
cover (Fig. 29).CAUTION: If housing cover is not installed within 3
to 5 minutes, the cover must be cleaned and new
RTV applied. Failure to heed caution may result in
damage.
(2) Install cover and identification tag. Tighten
cover bolts in a criss-cross pattern to 41 N´m (30 ft.
lbs.).
(3) Fill differential to specifications.
(4) Install fill plug.
DIFFERENTIAL
REMOVAL
(1) Remove filler plug from the differential cover.
(2) Remove differential cover and drain the lubri-
cant.
(3) Clean housing cavity with flushing oil, light
engine oil or a lint free cloth.
NOTE: Do not use steam, kerosene or gasoline to
clean the housing.
(4) Remove axle shafts.
(5) Remove RWAL/ABS sensor from housing.
NOTE: Side play resulting from bearing races being
loose on case hubs requires replacement of the dif-
ferential case.
(6) Mark differential housing and bearing caps for
installation reference (Fig. 30).
(7) Remove bearing threaded adjuster lock from
each bearing cap.
(8) Loosen differential bearing cap bolts.
Fig. 29 COVER SEALANT
1 - SEALANT
2 - DIFFERENTIAL COVER
Fig. 30 REFERENCE MARKS
1 - REFERENCE MARKS
2 - REFERENCE MARK
3 - BEARING CAPS
DRREAR AXLE - 9 1/4 3 - 97
PINION SEAL (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.
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 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.
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 - 10 1/2 AA 3 - 113
REAR AXLE - 10 1/2 AA (Continued)

INSTALLATION
(1) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.
CAUTION: Do not use water, steam, kerosene or
gasoline for cleaning.
(2) Lubricate differential case bearing.
(3) Install differential case with bearings cups into
the housing.
NOTE: A light coat of grease on the cups will hold
them in place during installation.
(4) Install bearing caps and bolts (Fig. 36). Tighten
the bearing cap bolts finger-tight.
NOTE: Do not torque bearing cap and bolts at this
time.
(5) 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.
(6) Holding the differential case toward the pinion
gear, turn bearing adjusters with Spanner Wrench
8883 until they make contact with the differential
bearings/cups.
(7) Back off the ring gear side adjuster 4 holes, to
obtain initial ring gear backlash.
(8) Install ring gear side adjuster lock and bolt. Do
not tighten adjuster lock bolt at this time.(9) Tighten pinion gear side adjuster firmly
against the differential case bearing cup.
(10) Rotate the pinion several times to seat the dif-
ferential bearings.
(11) Loosen pinion gear side adjuster until it is no
longer in contact with the bearing cup.
(12) Tighten pinion gear side adjuster until it just
makes contact with the bearing cup.
(13) Tighten pinion gear side adjuster an addi-
tional:
²New Bearings6 Adjuster Holes
²Original Bearings4 Adjuster Holes
(14) Install pinion gear side adjuster lock and bolt.
Do not tighten adjuster lock bolt at this time.
(15) Tighten bearing cap bolts to 165 N´m (122 ft.
lbs.).
(16) Tighten adjuster lock bolts to 25 N´m (18 ft.
lbs.) (Fig. 37).
(17) Measure ring gear backlash and check gear
tooth contact pattern. Refer to Adjustments for pro-
cedure.
(18) Install axle shafts.
(19) Install differential housing gasket and cover.
Tighten cover bolts to 40 N´m (30 ft. lbs.).
(20) Fill axle with lubricant, refer to Lubrication &
Maintenance for capacity and lubricant type.
(21) Install fill plug and tighten to 32 N´m (24 ft.
lbs.).
Fig. 36 CASE BEARING CAP
1 - DIFFERENTIAL HOUSING
2 - BEARING CAP
3 - ADJUSTERFig. 37 ADJUSTER LOCK BOLT
1 - DIFFERENTIAL CASE
2 - ADJUSTER LOCK
3 - ADJUSTER LOCK BOLT
4 - BEARING CAP BOLT
3 - 130 REAR AXLE - 10 1/2 AADR
DIFFERENTIAL (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.
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 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.
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 - 11 1/2 AA 3 - 141
REAR AXLE - 11 1/2 AA (Continued)