1993 DODGE TRUCK check engine

0
- 28
LUBRICATION
AND
MAINTENANCE

•
CHASSIS AND BODY

page

Body
Component Mechanisms
32
Front
Suspension
Ball
Joints
28

Front
Wheel Bearings
29

Headlamps
32

Lower
and
Upper Suspension
Arm
Bushings
.... 30

Manual
Steering Gear
28

STEERING
LINKAGE

INSPECTION When
a
vehicle
is
raised
for
maintenance under
the vehicle,
all
steering components should
be
checked.
LUBRICATION SCHEDULE The steering linkage
is
lubricated with
a
chassis
lubricant. However,
it is
recommended that
the
link­
age
be
inspected
and
lubricated after each:
•
24 000 km
(15,000 miles) interval
or
every
6

months,
for 2WD
vehicles subject
to the
LIGHT
DUTY CYCLE Maintenance Schedule
•
9 600 km
(6,000 miles) interval
or
every
6
months,
for
2WD
vehicles subject
to the
HEAVY DUTY
CY­
CLE Maintenance Schedule
•
12 000 km
(7,500 miles) interval
or
every
6

months,
for 4WD
vehicles subject
to the
LIGHT DUTY CYCLE Maintenance Schedule
•
9 600 km
(6,000 miles) interval
or
every
6
months,
for
4WD
vehicles subject
to the
HEAVY DUTY
CY­
CLE Maintenance Schedule.
LUBRICATION (1) Inspect
the
steering linkage
for
looseness
and

excessive wear. (2) Replace,
all
ruptured seals
and
damaged steer­
ing linkage components. Damaged seals should
be re­

placed
to
prevent leakage
and
contamination
of the
lubricant.

CAUTION:
Use
care
to
prevent lubricant from
con­

tacting
the
brake rotors.

(3) Lubricate
the
steering linkage:
• Clean
the
Zerk type lubrication fittings
on the tie-

rod
and
center link ball-stud ends
• Lubricate
the
ball studs with MOPAR®Multi-Mile- age Lubricant
• Wipe
the
excess lubricant from
the
exterior sur­
faces
of the
ball joints
page

Power
Brake System
30
Power
Steering System
. . 29

Rear
Wheel Bearings
30

Speedometer Cable
33

Steering Linkage
28

Tires
32

FRONT
SUSPENSION
BALL JOINTS

INSPECTION When
a
vehicle
is
raised
for
lubrication/general
maintenance,
the
ball joints should
be
inspected.
LUBRICATION SCHEDULE The front suspension ball joints
are
lubricated dur­
ing manufacture with
a
long-life chassis lubricant.
However,
it is
recommended that
the
ball joints
be

inspected
and the
studs lubricated:
•
At
each
36 000 km
(22,500 miles) interval
or
every
2 years,
for
vehicles subject
to the
LIGHT DUTY
CY­
CLE Maintenance Schedule
•
At
each
9 600 km
(6,000 miles) interval
or
every
2

years,
for
vehicles subject
to the
HEAVY DUTY
CY­
CLE Maintenance Schedule.
4WD vehicles that
are
frequently driven
off-

road should
be
lubricated
at
every engine
oil
change.
LUBRICATION (1) Inspect
the
front suspension. Examine
the
ball
studs
for
looseness
and
excessive wear. (2) Replace
all
torn ball-stud seals
and
damaged
ball joints. Damaged seals should
be
replaced
to
pre­ vent leakage
and
contamination.

CAUTION:
Use
care
to
prevent lubricant from
con­

tacting
the
brake rotors.

(3) Lubricate
the
ball studs:
• Clean
the
Zerk type lubrication fittings
on the

ball-stud ends
• Lubricate
the
ball studs with MOPAR®Multi-Mile-age Lubricant
• Wipe
the
excess lubricant from
the
exterior sur­
faces
of the
ball joints

MANUAL
STEERING
GEAR

LUBRICATION Manual steering gears
are
permanently lubricated
during manufacture. Periodic lubrication
is not
nec­
essary.

•

LUBRICATION
AND
MAINTENANCE
0 - 29
POWER STEERING SYSTEM

SERVICE SCHEDULE

FLUID
LEWEL

WARNING.
THE
POWER
STEERING
FLUID LEVEL
SHOULD
ALWAYS
BE
CHECKED
WITH THE EN­

GINE
OFF TO
PREVENT
PERSONAL
INJURY.

The power steering fluid should be checked when­
ever the engine is being serviced for other reasons. Clean the outside of the cap before removing. The
fluid should be at the proper level indicated on cap dipstick (Fig. 1).

Fig.
1
Power
Steering Reservoir & Cap—Typical
The reservoir fluid level can be determined with
the fluid either hot or cold. If the fluid level is below
the FULL HOT or FULL COLD marks on the dip­ stick, add power steering fluid. The dipstick is at­
tached to the reservoir cap (Fig. 1).
FLUID SPECIFICATION MOPAR03)Power Steering Fluid is highly recom­
mended.

FRONT
WHEEL BEARINGS
INSPECTION/LUBRICATION SCHEDULE

2WD
VEHICLES
It is recommended that 2WD front wheel bearings
be inspected for proper lubrication whenever the
brake rotors are removed or at least: • At each 39 000 km (24,000 miles) interval for ve­
hicles subject to the LIGHT DUTY CYCLE Mainte­ nance Schedule • At each 36 000 km (22,500 miles) interval for ve­
hicles subject to the HEAVY DUTY CYCLE Mainte­ nance Schedule The bearings should be cleaned and re-packed
with a high temperature, multi-purpose EP lu­
bricant.
4WD
VEHICLES

It is recommended that 4WD front wheel bearings
be inspected for proper lubrication whenever the
brake rotors are removed or at least:
• At each 24 000 km (15,000 miles) interval for ve­
hicles subject to the LIGHT DUTY CYCLE Mainte­ nance Schedule
• At each 19 000 km (12,000 miles) interval for ve­
hicles subject to the HEAVY DUTY CYCLE Mainte­ nance Schedule
For vehicles used for extensive off-road, 4WD
operation, the front wheel bearings should be in­ spected every 1 600 km (1,000 miles).
The bearings should be cleaned and re-packed
with a high temperature, multi-purpose EP lu­
bricant whenever the disc brake rotors are re­ surfaced.
INSPECTION If the lubricant:
• Is not sufficient
• Contaminated with foreign particles
• Appears dry or has been contaminated with water
to produce a milky appearance, the bearings should
be cleaned and re-packed with lubricant.

CAUTION:
Do not add
lubricant
to the
wheel
bear­
ings.
Re-pack completely. Mixing
of
different
types
of lubricants
in
wheel
bearings should
be
avoided.
This could possibly result
in
excessive thinning
and
leakage
of the
lubricant.

LUBRICATION (1) Discard the original seal.
(2) Clean the original lubricant from the bearings
and from the hub cavity (Figs. 2 and 3).
(3) Inspect the bearing rollers for indications of
pitting. Light bearing roller discoloration is consid­ ered normal. A wheel bearing must be replaced if any serious damage exists.
(4) Re-pack the bearings with a high temperature,
multi-purpose NLGI GC-LB lubricant. The use of a
bearing packer is recommended. A small amount of fresh lubricant also should be added to the hub cav­ ity.
BEARING INSTALLA TION/ADJUSTMENT (1) Install the hub/rotor (with inner bearing and
seal) on steering knuckle spindle.
(2) Install the outer bearing, the thrust washer
and the nut.
(3) Tighten wheel bearing nut to 27-34 N^m (240-
300 in. lbs.) torque while rotating hub/rotor. This
will seat the bearings.
(4) Loosen the nut 1/4 of-a-turn (90°), then tighten
it finger-tight.

0
- 32
LUBRICATION
AND
MAINTENANCE

•

Fig.
5 Parking Brake Ratio Lever Lubrication (2) Note any indication of brake overheating,
wheel dragging or the vehicle pulling to one side.
(3) Evaluate any performance complaints received
from the owner/operator. (4) Repair the brake system as necessary (refer to
Group 5—Brakes for additional information and ser­
vice procedures).

BODY
COMPONENT
MECHANISMS
LUBRICATION REQUIREMENTS
All operating mechanisms and linkages should be
lubricated when necessary. This will maintain ease of operation and provide protection against rust and
excessive wear. The door weatherstrip seals should
be lubricated to prolong their life as well as to im­ prove door sealing.

LUBRICANT SPECIFICATIONS
All applicable exterior and interior vehicle operat­
ing mechanisms should be:
• Inspected • Cleaned
• All the pivoting/sliding contact areas on the mech­ anisms should then be lubricated.
MOPAR®Multi-Mileage Lubricant or an equiva­
lent, should be used to lubricate the mechanisms.
The door weatherstrip seals should be lubricated
with silicone lubricant spray. Refer to the Body Lu­
bricant Specifications chart below for additional lu­
bricant applications.

LUBRICATION
(1) When necessary, lubricate the cab and cargo
box operating mechanisms with the specified lubri­
cants.

(2) Apply silicone lubricant to a cloth and wipe it
on door seals to avoid over-spray that can soil pas­
senger clothing. (3) Before applying lubricant, the component
should be wiped clean. After lubrication, any excess
lubricant should be removed.
(4) The hood latch, latch release mechanism, latch
striker and safety latch should be lubricated periodi­
cally.
(5) The door lock cylinders should be lubricated 2
times each year (preferably autumn and spring): • Spray a small amount of lock cylinder lubricant di­
rectly into the lock cylinder
• Apply a small amount to the key and insert it into
the lock cylinder • Rotate it to the locked position and then back to
the unlocked position several times
• Remove the key. Wipe the lubricant from it with a
clean cloth to avoid soiling of clothing.

TIRES
RECOMMENDED MAINTENANCE
The condition of the tires should be inspected. The
inflation pressures tested/corrected at the same time as the engine oil is changed and the oil filter is re­
placed.
The tires/wheels should be rotated periodically to
ensure even tread wear. The tires/wheels should be
rotated at the first 12 000 km (7,500-miles) interval.
Thereafter, at each 24 000 km (15,000-miles) inter­
val.
INSPECTION
Inspect the tires for excessive wear, damage. Test
the tires for the recommended inflation pressure and adjust the pressure accordingly. Refer to the tire in­
flation pressure decal located on the left door face. Also to Group 22—Tires And Wheels for tire pres­sure charts, tire replacement, and treadwear indica­

tors.

ROTATION
Tires/wheels should be rotated according to the rec­
ommended interval. The first tire/wheel rotation is
the most important for establishing the prevention of uneven tread wear. After rotation, adjust the tire in­
flation pressure to the air pressure recommended on
the decal located on the left door face.
Refer to Group 22—Tires And Wheels for the rec­
ommended method of tire/wheel rotation.

HEADLAMPS

MAINTENANCE SCHEDULE
Every six months check the headlamp beams to en­
sure that the headlamp beams are correctly posi­
tioned.

AIM
ADJUSTMENT
Refer to Group 8L—Lamps for headlamp aim ad­
justment procedures.

•

FRONT
SUSPENSION
AND
AXLE
2 - 5 (4) Front wheels for excessive radial, lateral
runout and unbalance. Refer to Group 22, Wheels and Tires for diagnosis information.
(5) Suspension components for wear and noise. Check
components for correct torque. Refer to Groups 2 and 3, Suspension and Axle for additional information.

WHEEL
ALIGNMENT
MEASUREMENTS/ADJUSTMENTS
The front wheel alignment positions must be set to
the specified limits. This will prevent abnormal tire
tread wear. The equipment manufacturer's recommenda­
tions for use of their
equipment
should always
be followed. All
damaged
front suspension sys­
tem components
should
be replaced. Do not at­ tempt to straighten any
bent
component.

CAMBER AND CASTER-2WD VEHICLES Camber and caster angle adjustments involve repo­
sitioning the upper suspension arm cam adjustment
bolts (Fig. 2). Alignment adjustments are accom­
plished by loosening the nuts and changing the posi­
tion of the cam bolt.
(1) Remove all foreign material from the adjust­
ment bolt threads.
(2) Record the camber and caster measurements
before loosening the adjustment bolt nuts.
(3) The camber angle should be adjusted as near as
possible to the preferred angle. The caster should be
the same at both sides of the vehicle. Refer to the Specifications chart.
CAMBER AND CASTER—4WD VEHICLES For 4WD vehicles, the correct wheel camber (verti­
cal tilt) angle is factory preset at zero degree (0°).
Camber cannot be altered by adjustment.
CAUTION: Do not attempt to
adjust
the
camber
an­
gle by
heating
or bending the axle or any
suspen­

sion
component. If camber angle is
incorrect,
the
component(s)
causing
an
incorrect
angle must be replaced.
(1) It is important that the camber (vertical tilt)
angle be the same for both front wheels.
(2) The camber angle should be measured with ac­
curate wheel alignment equipment. The acceptable
range is -1° to +1°. Refer to the Specifications chart.
Road test the vehicle and observe the steering
wheel return-to-center position. Before road testing,
check
and
correct
the tire
inflation pressures. Inflate
both
of the front tires
with exactly the
same
pressure.
During the road test, make vehicle turns to both
the left and right. If the steering wheel returns to­
ward the center position unassisted, the caster angle is correct. However, if the steering wheel does not re­ turn toward the center position unassisted, an incor­
rect caster angle is probable.
(1) The caster angle is factory preset at positive
two degrees
(
+
2°).
The acceptable range is +1/2° to +
3
1/2°.
(2) The caster angle should be measured with ac­
curate wheel alignment equipment.
(3) Caster angle can be adjusted by installing ta­
pered shims between the front axle pads and the spring brackets. The caster angle should be adjusted
as near as possible to the preferred angle.
(4) Record the caster measurement before remov­
ing the original shims from the spring pads.
(5) The caster should be the same at both sides of
the vehicle. Refer to the Specifications chart.
RN1030

Fig.
2 Caster &
Camber
Adjustment Location—2WD
Vehicles

WHEEL TOE POSITION The wheel toe position adjustment should be the fi­
nal front wheel alignment adjustment. In all in­ stances, follow the equipment manufacturer's
recommended procedure.
(1) Secure the steering wheel with the front wheels
in the straight-ahead position. For vehicles equipped
with power steering, start the engine before straight­ ening the wheels.
With power steering, the engine should be op­
erating during the wheel toe position adjust­
ment.
(2) Loosen the tie rod adjustment sleeve clamp
bolts (Fig. 3).
(3) Adjust the wheel toe position by rotating the
tie rod adjustment sleeve (Fig. 3). Rotate each tie-rod end in the direction of
sleeve rotation during the adjustment (Fig. 3).
This will ensure that both tie-rod ends are at the center of their travel.
(4) If applicable, turn the ignition switch off.

2 - 28
FRONT
SUSPENSION
AND
AXLE

DISCONNECT
AXLE/SHIFT
MOTOR
DIAGNOSIS
TWO-WHEEL DRIVE
OPERATION
DIAGNOSIS
FOUR-WHEEL DRIVE
INDICATOR
LIGHT
WILL NOT GO OUT WHEN
TRANSFER CASE SELECTOR
IS
MOVED FROM 4H TO 2H POSITION.

RAISE
VEHICLE SO ALL FOUR WHEELS ARE
FREE
TO ROTATE. INSPECT INDICATOR
SWITCH AND WIRING ON SHIFT MOTOR HOUSING FOR DAMAGE AND SHORT-CIRCUIT.

REPAIR
AS NECESSARY.
YES
i
START ENGINE DEPRESS BRAKE
PEDAL.
PLACE TRANSFER

CASE
SELECTOR IN 2H POSITION AND TRANSMISSION IN
DRIVE
(AUTOMATIC)
OR FIRST

GEAR
(MANUAL). EASE OFF FROM
BRAKE
AND LET WHEELS ROTATE SLOWLY. TEST COMPLETE
FRONT DRIVE SHAFT DOES
NOT ROTATE. FRONT DRIVE
SHAFT ROTATES.
FOUR-WHEEL DRIVE INDICATOR
LIGHT
REMAINS
ON. INSPECT TRANSFER

CASE
LINKAGE.

PLACE
TRANSMISSION IN NEUTRAL. TEST FOR VACUUM
IN VACUUM HOSE

THAT
CONNECTS TO INBOARD SHIFT MOTOR PORT.
(VACUUM SHOULD BE
BETWEEN 10-20 IN. HG.)
CHECK
TRANSFER

CASE.
REPAIR

AS
NECESSARY.
NO VACUUM
OR LOW VACUUM. VACUUM OK
INSPECT INTAKE MANIFOLD
VACUUM SUPPLY HOSE CONNECTION,
TRANSFER CASE VACUUM SWITCH
CONNECTION, VACUUM RESERVOIR, AND SHIFT SYSTEM VACUUM HOSES
FOR PROPER CONNECTION, RESTRICTION,
AIR LEAKS, AND DAMAGE. REPAIR OR REPLACE
AS
NECESSARY. STOP ENGINE
—r~
FRONT AXLE

DISCONNECTS.

INSPECT VACUUM

HOSES
FOR AIR LEAKS, KINKS, ETC.
REPAIR
AS NECESSARY. FRONT AXLE

DOES
NOT
DISCONNECT.
REMOVE SHIFT MOTOR
HOUSING COVER. CONNECT VACUUM PUMP TO
SHIFT MOTOR PORT.

REPLACE
SHIFT MOTOR
IF ARMATURE DOES
NOT MOVE IN AND OUT FREELY. FRONT AXLE
WILL NOT DISCONNECT.

J9002-95
REMOVE SHIFT MOTOR HOUSING
COVER. INSPECT SHIFT FORK, COLLAR, AND AXLE SHAFTS.
REPAIR
OR REPLACE AS
NECESSARY

FRONT
SUSPENSION AND
AXLE
2 - 29
DISCONNECT AXLE/SHIFT MOTOR DIAGNOSIS
(CONT'D)

FOUR-WHEEL
DRIVE
OPERATION
DIAGNOSIS
FOUR-WHEEL DRIVE INDICATOR
LIGHT
DOES NOT
LIGHT
WHEN TRANSFER CASE SELECTOR IN 4H OR 4L POSITION.

RAISE
VEHICLE SO ALL FOUR
WHEELS ARE FREE TO ROTATE.
START ENGINE, DEPRESS BRAKE PEDAL.

PLACE
TRANSFER CASE SELECTOR IN 4H
POSITION AND TRANSMISSION LEVER IN DRIVE
(AUTOMATIC)
OR IN FIRST GEAR
(MANUAL) TO CONFIRM TRANSFER CASE ENGAGEMENT IN 4H. LET WHEELS ROTATE SLOWLY.
FRONT DRIVE SHAFT DOES
NOT ROTATE. FRONT DRIVE
SHAFT TURNS.
INSPECT TRANSFER
CASE
LINKAGE.

CHECK
TRANSFER
CASE.
REPAIR AS
NECESSARY.
FRONT AXLE
CONNECTS.
FOUR-WHEEL DRIVE INDICATOR
LIGHT
DOES
NOT LIGHT.
INSPECT FWD INDICATOR SWITCH, WIRING, AND
LAMP FOR DAMAGE.

REPAIR
AS NECESSARY. RECOMMENDATION:

CHECK
VACUUM SHIFT SYSTEM FOR PROPER
OPERATION.
PLACE
TRANSMISSION
LEVER IN NEUTRAL POSITION. FRONT AXLE

DOES
NOT
CONNECT.
REMOVE VACUUM HOSES FROM AXLE SHIFT MOTOR PORTS.
START ENGINE. TEST FOR VACUUM AT HOSE REMOVED FROM
OUT­

BOARD
PORT ON SHIFT MOTOR,
SHOULD BE BETWEEN 10-20 IN HG.
NO VACUUM
OR LOW VACUUM. STOP ENGINE
H VACUUM OK
INSPECT INTAKE MANIFOLD
VACUUM SUPPLY HOSE CONNECTION, TRANSFER CASE VACUUM SWITCH
CONNECTION, VACUUM RESERVOIR, AND SHIFT
SYSTEM VACUUM HOSES FOR PROPER CONNECTION, RESTRICTION, LEAKS, AND DAMAGE.
REPAIR
OR REPLACE AS NECESSARY. CONNECT A VACUUM PUMP
TO THE OUTBOARD
SHIFT MOTOR PORT.
APPLY 15 INCHES HG. VACUUM AND ROTATE LEFT WHEEL.
NO VACUUM FRONT AXLE
CONNECTED.

CHECK
TRANSFER CASE
VACUUM SWITCH. REPLACE OR REPAIR IF SWITCH
PLUNGER IS DIFFICULT TO MOVE OR BINDS. FRONT AXLE

DOES
NOT
CONNECT.
INSPECT VACUUM HOSES FOR LEAKS, KINKS, ETC.
REPAIR
AS NECESSARY. REMOVE SHIFT MOTOR
HOUSING COVER. CONNECT VACUUM PUMP TO
SHIFT MOTOR PORT.

REPLACE
SHIFT MOTOR
IF ARMATURE DOES
NOT MOVE IN AND OUT FREELY. REMOVE SHIFT MOTOR HOUSING
COVER. INSPECT SHIFT FORK, COLLAR, AND AXLE SHAFTS.
REPAIR
OR REPLACE AS
NECESSARY.
*
REMOVE SHIFT MOTOR HOUSING
COVER. INSPECT SHIFT FORK, COLLAR, AND AXLE SHAFTS.
REPAIR
OR REPLACE AS
NECESSARY.
FRONT AXLE
WILL NOT CONNECT.
REMOVE SHIFT MOTOR HOUSING
COVER. INSPECT SHIFT FORK, COLLAR, AND AXLE SHAFTS.
REPAIR
OR REPLACE AS
NECESSARY.
FRONT AXLE
WILL NOT CONNECT.
REMOVE SHIFT MOTOR HOUSING
COVER. INSPECT SHIFT FORK, COLLAR, AND AXLE SHAFTS.
REPAIR
OR REPLACE AS
NECESSARY.

J9002-96

3
- 6
REAR SUSPENSION
AND
AXLE

•

NUT PIPE
SOCKET
WRENCH
(DRIVER)

FLAT
THREADED
WASHER
ROD
J8917-20

Fig.
6
Spring
Eye
Bushing
Removal
(3) Align
the
bushing with
the
spring
eye and

tighten
the nut
located
at the
socket wrench
end of

the threaded
rod.
Tighten until
the
bushing
is
forced into
the
spring
eye.

The bushing must
be
centered
in the
spring

eye.
The
ends
of the
bushing must
be
flush
or
slightly recessed within
the end
surfaces
of the

spring
eye.
8ERW1GE DIAGNOSIS
INDEX
page

Driveline
Snap
8

Gear
and
Bearing Noise
7

General
Information
6
Limited
Slip
Differential
8
page
Low Speed Knock
.........................
8
Rear
Axle
Alignment
.......................
7

Tire
Noise
7
Vibration
8

GENERAL INFORMATION
Axle bearing problem conditions
are
usually caused
by: • Insufficient
or
incorrect lubricant
• Foreign matter/water contamination
• Incorrect bearing preload torque adjustment When serviced,
the
bearings must
be
cleaned thor­
oughly. They should
be
dried with lint-free shop tow­

els.
Never
dry
bearings with compressed
air.

This will overheat them
and
brinell
the
bearing surfaces. This will result
in
noisy operation after
repair. Axle gear problem conditions
are
usually
the
result

of:

• Insufficient lubrication
• Incorrect
or
contaminated lubricant
• Overloading (excessive engine torque)
• Incorrect clearance
or
backlash adjustment Insufficient lubrication
is
usually
the
result
of a

housing cover leak.
It can
also
be
from worn axle shaft
or
pinion gear seals. Check
for
cracks
or
porous
areas
in the
housing
or
tubes.
Using
the
wrong lubricant will cause overheating
and gear failure. Gear tooth cracking
and
bearing
spalling
are
indicators
of
this.
Axle component breakage
is
most often
the
result

of:

• Severe overloading
• Insufficient lubricant
• Incorrect lubricant • Improperly tightened components
Common causes
of
overloading
is
from full-throttle
acceleration. Overloading occurs when towing
heavier than normal loads. Component breakage
can
occur when
the
wheels
are
spun excessively. Insuffi­
cient
or
incorrect lubricants contribute
to
breakage
through overheating. Loose differential components can also cause breakage. Incorrect bearing preload
or
gear backlash will
not

result
in
component breakage. Mis-adjustment will
produce enough noise
to
cause service repair before
a

3
- 8
REAR SUSPENSION
AND
AXLE

• 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 gear shaft bore will also cause low speed knock.

VIBRATION
Vibration at the rear of the vehicle is usually
caused by a:
• Damaged drive shaft
• Missing drive shaft balance weight
• Worn, out-of-balance wheel and tires
• Loose wheel lug nuts
• Worn U-joint • Loose spring U-bolts
• Loose/broken rear springs or shackles
• Damaged axle shaft bearings
• Loose pinion gear nut
• Excessive pinion yoke run out
• Bent axle shaft Check for loose or damaged front-end components
or engine/transmission mounts. These components
can contribute to what appears to be a rear-end vi­
bration. Do not overlook engine accessories, brackets and drive belts. All driveline components should be examined be­
fore starting any repair. Refer to Group 22, Wheels and Tires for additional
information.

DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged), can be caused by: • High engine idle speed
• Loose engine/transmission/transfer case mounts

9
Worn U-joints
• Loose spring shackles or U-bolts
• Loose pinion gear nut and yoke
• Excessive ring gear backlash
• Excessive differential side gear-to-case clearance A worn bushing in the transmission extension
housing can also cause noise. The source of a snap or a clunk noise can be deter­
mined with the assistance of a helper. Raise the ve­
hicle 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.

LIMITED
SLIP DIFFERENTIAL
Under normal traction conditions, engine torque is
divided evenly. With low-traction surfaces, engine
torque is transferred to the wheel with the most tire
traction. When diagnosing a limited-slip differential
problem condition, the wheel with the least traction can continue spinning. The most common problem is a chatter noise when
turning corners. Check for incorrect or contaminated lubricant. Replace the gear lubricant if necessary.
• With Sure-Grip differentials add a container of
MOPAR® Hypoid Gear Additive This will correct the condition in most instances. If
the chatter persists, clutch damage could have oc­ curred. 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.