suspension DODGE RAM 2003 Service Repair Manual

GROUP TAB LOCATOR
Introduction
0Lubrication & Maintenance
2Suspension
3Differential & Driveline
5Brakes
6Clutch
7Cooling
8AAudio
8BChime/Buzzer
8EElectronic Control Modules
8FEngine Systems
8GHeated Systems
8HHorn
8IIgnition Control
8JInstrument Cluster
8LLamps
8MMessage Systems
8NPower Systems
8ORestraints
8PSpeed Control
8QVehicle Theft Security
8RWipers/Washers
8WWiring
9Engine
11Exhaust System
13Frame & Bumpers
14Fuel System
19Steering
21Transmission and Transfer Case
22Tires/Wheels
23Body
24Heating & Air Conditioning
25Emissions Control
Component and System Index
Service Manual Comment Forms (Rear of Manual)

HOISTING
STANDARD PROCEDURE - HOISTING
Refer to the Owner's Manual for emergency vehicle
lifting procedures.
WARNING: THE HOISTING AND JACK LIFTING
POINTS PROVIDED ARE FOR A COMPLETE VEHI-
CLE. WHEN A CHASSIS OR DRIVETRAIN COMPO-
NENT IS REMOVED FROM A VEHICLE, THE
CENTER OF GRAVITY IS ALTERED MAKING SOME
HOISTING CONDITIONS UNSTABLE. PROPERLY
SUPPORT (Fig. 5) OR SECURE VEHICLE TO HOIST-
ING DEVICE WHEN THESE CONDITIONS EXIST.
FLOOR JACK
When properly positioned, a floor jack can be used
to lift a vehicle (Fig. 6). Support the vehicle in the
raised position with jack stands at the front and rear
ends of the frame rails (Fig. 5).
CAUTION: Do not lift vehicle with a floor jack posi-
tioned under:
²An axle tube.
²A body side sill.
²A steering linkage component.²A drive shaft.
²The engine or transmission oil pan.
²The fuel tank.
²A front suspension arm.
NOTE: Use the correct frame rail lifting locations
only (Fig. 7) and (Fig. 8).
HOIST
A vehicle can be lifted with:
²A single-post, frame-contact hoist.
²A twin-post, chassis hoist.
²A ramp-type, drive-on hoist.
NOTE: When a frame-contact type hoist is used,
verify that the lifting pads are positioned properly
(Fig. 6). The forward lifting pads should be posi-
tioned against the forward flange of the transmis-
sion crossmember brackets at the bottom of the
frame rail (Fig. 7). The real lifting pads should be
wedged between the forward flange of the leaf
spring bracket and the frame rail (Fig. 8). Safety
stands should be placed under the frame rails at
the front and rear ends (Fig. 5).
Fig. 5 Safety Stands
1 - SAFETY STANDS
Fig. 6 Vehicle Lifting Locations
0 - 14 LUBRICATION & MAINTENANCEDR

SUSPENSION
TABLE OF CONTENTS
page page
WHEEL ALIGNMENT......................1
FRONT - INDEPENDENT FRONT SUSPENSION..8FRONT - LINK/COIL......................28
REAR.................................38
WHEEL ALIGNMENT
TABLE OF CONTENTS
page page
WHEEL ALIGNMENT
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING - PRE-ALIGNMENT
INSPECTION..........................2
STANDARD PROCEDURE
STANDARD PROCEDURE - HEIGHT
MEASUREMENT - 4WD (LD)..............3
STANDARD PROCEDURE - HEIGHT
ADJUSTMENT - 4WD (LD)................3
STANDARD PROCEDURE - CAMBER AND
CASTER ADJUSTMENT..................4STANDARD PROCEDURE - TOE
ADJUSTMENT.........................4
STANDARD PROCEDURE - CAMBER,
CASTER AND TOE ADJUSTMENT..........4
STANDARD PROCEDURE - ALIGNMENT
LINK/COIL SUSPENSION.................5
SPECIFICATIONS
ALIGNMENT..........................6
SPECIAL TOOLS
WHEEL ALIGNMENT....................7
WHEEL ALIGNMENT
DESCRIPTION
NOTE: Suspension components with rubber/ure-
thane bushings should be tightened with the vehi-
cle at normal ride height. It is important to have the
springs supporting the weight of the vehicle when
the fasteners are torqued. If springs are not at their
normal ride position, vehicle ride comfort could be
affected and premature bushing wear may occur.
Wheel alignment involves the correct positioning of
the wheels in relation to the vehicle. The positioning
is accomplished through suspension and steering
linkage adjustments. An alignment is considered
essential for efficient steering, good directional stabil-
ity and to minimize tire wear. The most important
measurements of an alignment are caster, camber
and toe (Fig. 1).
CAUTION: Never attempt to modify suspension or
steering components by heating or bending.
Fig. 1 Wheel Alignment Measurements
1 - FRONT OF VEHICLE
2 - STEERING AXIS INCLINATION
3 - PIVOT POINT
4 - TOE-IN
DRSUSPENSION 2 - 1

OPERATION
²CASTERis the forward or rearward tilt of the
steering knuckle from vertical. Tilting the top of the
knuckle forward provides less positive caster. Tilting
the top of the knuckle rearward provides more posi-
tive caster. Positive caster promotes directional sta-
bility. This angle enables the front wheels to return
to a straight ahead position after turns (Fig. 1)
²CAMBERis the inward or outward tilt of the
wheel relative to the center of the vehicle. Tilting the
top of the wheel inward provides negative camber.
Tilting the top of the wheel outward provides positive
camber. Incorrect camber will cause wear on the
inside or outside edge of the tire (Fig. 1)
²TOEis the difference between the leading inside
edges and trailing inside edges of the front tires.
Wheel toe position out of specification cause's unsta-
ble steering, uneven tire wear and steering wheel off-
center. The wheel toe position is thefinalfront
wheel alignment adjustment (Fig. 1)
²THRUST ANGLEis the angle of the rear axle
relative to the centerline of the vehicle. Incorrect
thrust angle can cause off-center steering and exces-sive tire wear. This angle is not adjustable, damaged
component(s) must be replaced to correct the thrust
angle (Fig. 1)
DIAGNOSIS AND TESTING - PRE-ALIGNMENT
INSPECTION
Before starting wheel alignment, the following
inspection and necessary corrections must be com-
pleted. Refer to Suspension and Steering System
Diagnosis Chart below for additional information.
(1) Inspect tires for size, air pressure and tread
wear.
(2) Inspect front wheel bearings for wear.
(3) Inspect front wheels for excessive radial or lat-
eral runout and balance.
(4) Inspect ball studs, linkage pivot points and
steering gear for looseness, roughness or binding.
(5) Inspect suspension components for wear and
noise.
(6) On 4x4 vehicles check suspension height (LD
only).
(7) Road test the vehicle.
SUSPENSION AND STEERING SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
FRONT END NOISE 1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Loose or worn steering or
suspension components.3. Tighten or replace components as
necessary.
EXCESSIVE PLAY IN
STEERING1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Loose or worn steering gear. 3. Replace steering gear.
FRONT WHEELS SHIMMY 1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Tires worn or out of balance. 3. Replace or balance tires.
4. Alignment. 4. Align vehicle to specifications.
VEHICLE INSTABILITY 1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Tire pressure. 3. Adjust tire pressure.
4. Alignment. 4. Align vehicle to specifications.
2 - 2 WHEEL ALIGNMENTDR
WHEEL ALIGNMENT (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE STEERING
EFFORT1. Loose or worn steering gear. 1. Replace steering gear.
2. Column coupler binding. 2. Replace coupler.
3. Tire pressure. 3. Adjust tire pressure.
4. Alignment. 4. Align vehicle to specifications.
VEHICLE PULLS TO ONE
SIDE1. Tire pressure. 1. Adjust tire pressure.
2. Tire. 2. Criss-Cross Front Tires.
3. Alignment. 3. Align vehicle to specifications.
4. Loose or worn steering or
suspension components.4. Tighten or replace components as
necessary.
5. Radial tire lead. 5. Rotate or replace tire as necessary.
6. Brake pull. 6. Repair brake as necessary.
7. Weak or broken spring. 7. Replace spring.
8. Ride height (LD) 4WD only. 8. Measure and adjust ride height. (LD
only)
STANDARD PROCEDURE
STANDARD PROCEDURE - HEIGHT
MEASUREMENT - 4WD (LD)
The vehicle suspension height MUST be measured
and adjusted before performing wheel alignment pro-
cedure. Also when front suspension components have
been replaced. This measure must be performed with
the vehicle supporting it's own weight and taken on
both sides of the vehicle.
(1) Inspect tires and set to correct pressure.
(2) Jounce the front of the vehicle.
(3) Measure and record the height from the ground
at the centerline of the rear lower control arm bolt
front tip (Fig. 2).
(4) Measure and record the height from the ground
at the front spindle centerline (Static Load Radius)
(Fig. 2).
(5) Subtract the first measurement from the sec-
ond measurement. The difference between the two
measurement should be 58 mm (2.3 inches) 3mm
(0.12 inches).
(6) If value is greater than 61 mm (2.4 inches),
tighten the torsion bar bolt until the specification is
achieved (Refer to 2 - SUSPENSION/WHEEL
ALIGNMENT - STANDARD PROCEDURE).
(7) If value is less than 55 mm (2.1 inches), loosen
the torsion bar bolt until the specification is achieve-
d,(Refer to 2 - SUSPENSION/WHEEL ALIGNMENT
- STANDARD PROCEDURE).
(8) Repeat the previous steps until the ride height
is within specifications.
STANDARD PROCEDURE - HEIGHT
ADJUSTMENT - 4WD (LD)
The vehicle suspension height MUST be measured
and adjusted before performing wheel alignment pro-
cedure (Refer to 2 - SUSPENSION/WHEEL ALIGN-
MENT - STANDARD PROCEDURE). Also when
front suspension components have been replaced.
This measurement must be performed with the vehi-
cle supporting it's own weight and taken on both
sides of the vehicle.
Fig. 2 HEIGHT MESUREMENT
1 - HEIGHT FROM THE GROUND AT THE FRONT SPINDLE
CENTERLINE (STATIC LOAD RADIUS)
2 - CENTERLINE OF THE REAR LOWER CONTROL ARM BOLT
FRONT TIP
3 - GROUND LINE
DRWHEEL ALIGNMENT 2 - 3
WHEEL ALIGNMENT (Continued)

To adjust the vehicle height turn the torsion bar
adjustment bolt CLOCKWISE to raise the vehicle
and COUNTER CLOCKWISE to lower the vehicle.
CAUTION: ALWAYS raise the vehicle to the correct
suspension height, NEVER lower the vehicle to
obtain the correct suspension height. If the vehicle
suspension height is too high, lower the vehicle
below the height specification. Then raise the vehi-
cle to the correct suspension height specification.
This will insure the vehicle maintains the proper
suspension height.
NOTE: If a height adjustment has been made, per-
form height measurement again on both sides of
the vehicle.
STANDARD PROCEDURE - CAMBER AND
CASTER ADJUSTMENT
NOTE: 4X4 (LD) SUSPENSION HEIGHT MEASURE-
MENT MUST BE PERFORMED BEFORE AN ALIGN-
MENT.
NOTE: When the upper control arm pivot bolts are
loosened the upper control arm will normally go
inwards toward the frame automatically with the
weight of the vehicle.
Camber and caster angle adjustments involve
changing the position of the upper control arm incon-
junction with the slotted holes in the frame brackets,
Install special tool 8876 between the top of the upper
control arm bracket and the upper control arm (on
1500 series 4X2 & 4X4). Install special tool 8876
between the bottom of the upper control arm bracket
pressing the tool against the frame and the upper
control arm (on 2500/3500 series 4X2) in order to
move the upper control arm outwards for proper
adjustment with the vehicle at normal ride height
(Fig. 3).
STANDARD PROCEDURE - TOE ADJUSTMENT
4X4 SUSPENSION HEIGHT MESUREMENT
MUST BE PERFORMED BEFORE AN ALIGN-
MENT.
The wheel toe position adjustment is the final
adjustment.
(1) Start the engine and turn wheels both ways
before straightening the wheels. Secure the steering
wheel with the front wheels in the straight-ahead
position.
(2) Loosen the tie rod jam nuts.NOTE: Each front wheel should be adjusted for
one-half of the total toe position specification. This
will ensure the steering wheel will be centered
when the wheels are positioned straight-ahead.
(3) Adjust the wheel toe position by turning the
inner tie rod as necessary (Fig. 4).
(4) Tighten the tie rod jam nut to 75 N´m (55 ft.
lbs.).
(5) Verify the specifications
(6) Turn off engine.
STANDARD PROCEDURE - CAMBER, CASTER
AND TOE ADJUSTMENT
NOTE: 4X4 (LD) SUSPENSION HEIGHT MEASURE-
MENT MUST BE PERFORMED BEFORE AN ALIGN-
MENT.
Camber and caster angle adjustments involve
changing the position of the upper control arm with
the slots in the frame brackets using special tool
8876 to move the upper control arm outwards for
proper adjustment. (Fig. 3)
NOTE: When the upper control arm pivot bolts are
loosened the upper control arm will normally go
inwards toward the frame automatically with the
weight of the vehicle.
CASTER
Moving the front or rear position of the upper con-
trol arm in or out, will change the caster angle and
camber angle significantly. To maintain the camber
Fig. 3 CASTER & CAMBER ADJUSTMENT
1 - FRONT PIVOT BOLT
2 - REAR PIVOT BOLT
3 - SLOTTED HOLES FOR ADJUSTMENT OF CASTER &
CAMBER
4 - UPPER CONTROL ARM
2 - 4 WHEEL ALIGNMENTDR
WHEEL ALIGNMENT (Continued)

angle while adjusting caster, move one pivot bolt of
the upper control arm in or out. Then move the other
pivot bolt of the upper control arm in the opposite
direction. Install special tool 8876 between the top of
the upper control arm bracket and the upper control
arm (on 1500 series 4X2 & 4X4). Install special tool
8876 between the bottom of the upper control arm
bracket pressing the tool against the frame and the
upper control arm (on 2500/3500 series 4X2) in order
to move the upper control arm outwards for proper
adjustment with the vehicle at normal ride height
(Fig. 3).
To increase positive caster angle, move the rear
position of the upper control arm inward (toward the
engine). Move the front of the upper control arm out-
ward (away from the engine) slightly until the origi-
nal camber angle is obtained using special tool 8876
to move the upper control arm for proper adjustment.
(Fig. 3)
CAMBER
Move both pivot bolts of the upper control arm
together in or out. This will change the camber angle
significantly and little effect on the caster angle
using special tool 8876 to move the upper control
arm for proper adjustment. (Fig. 3)
After adjustment is made tighten the upper control
arm nuts to proper torque specification.
TOE ADJUSTMENT
The wheel toe position adjustment is the final
adjustment.
(1) Start the engine and turn wheels both ways
before straightening the wheels. Secure the steering
wheel with the front wheels in the straight-ahead
position.
(2) Loosen the tie rod jam nuts.
NOTE: Each front wheel should be adjusted for
one-half of the total toe position specification. This
will ensure the steering wheel will be centered
when the wheels are positioned straight-ahead.
(3) Adjust the wheel toe position by turning the
inner tie rod as necessary (Fig. 4).
(4) Tighten the tie rod jam nut to 75 N´m (55 ft.
lbs.).
(5) Verify the specifications
(6) Turn off engine.
STANDARD PROCEDURE - ALIGNMENT
LINK/COIL SUSPENSION
Before each alignment reading the vehicle should
be jounced (rear first, then front). Grasp each
bumper at the center and jounce the vehicle up and
down several times. Always release the bumper inthe down position.Set the front end alignment to
specifications while the vehicle is in its NOR-
MALLY LOADED CONDITION.
CAMBER:The wheel camber angle is preset and
is not adjustable.
CASTER:Check the caster of the front axle for
correct angle. Be sure the axle is not bent or twisted.
Road test the vehicle and make left and right turn.
Observe the steering wheel return-to-center position.
Low caster will cause poor steering wheel returnabil-
ity.
Caster can be adjusted by rotating the cams on the
lower suspension arm (Fig. 5).
TOE POSITION:The wheel toe position adjust-
ment should be the final adjustment.
Fig. 4 TIE ROD END
1 - JAM NUT
2 - TIE ROD - INNER
3 - TIE ROD END - OUTER
Fig. 5 ALIGNMENT ADJUSTMENT CAM
1 - BRACKET REINFORCEMENT
2 - ADJUSTING BOLT
3 - ADJUSTMENT CAM
DRWHEEL ALIGNMENT 2 - 5
WHEEL ALIGNMENT (Continued)

FRONT - INDEPENDENT FRONT SUSPENSION
TABLE OF CONTENTS
page page
FRONT - INDEPENDENT FRONT SUSPENSION
DESCRIPTION
DESCRIPTION........................9
DESCRIPTION........................9
SPECIFICATIONS
TORQUE CHART......................10
SPECIAL TOOLS
FRONT SUSPENSION..................11
BUSHINGS
REMOVAL
REMOVAL - LOWER CONTROL ARM
BUSHINGS - 4WD (LD).................12
REMOVAL - TORSION BAR
CROSSMEMBER BUSHING..............12
REMOVAL - LOWER CONTROL ARM
BUSHINGS - 2WD (LD).................12
INSTALLATION
INSTALLATION - LOWER CONTROL ARM
BUSHINGS - 4WD (LD).................13
INSTALLATION - TORSION BAR CROSS
MEMBER BUSHING....................14
INSTALLATION - LOWER CONTROL ARM
BUSHINGS - 2WD (LD).................14
HUB / BEARING
REMOVAL
REMOVAL - 4X4......................15
REMOVAL - 4X2......................16
INSTALLATION
INSTALLATION - 4X4...................16
INSTALLATION - 4X2...................17
KNUCKLE
DESCRIPTION.........................17
OPERATION...........................17
REMOVAL.............................17
INSTALLATION.........................18
LOWER BALL JOINT
DIAGNOSIS AND TESTING - LOWER BALL
JOINT..............................18
REMOVAL.............................18
INSTALLATION.........................19LOWER CONTROL ARM
REMOVAL
REMOVAL - 4X4 (LD)...................20
REMOVAL - 4X2......................20
INSTALLATION
INSTALLATION - 4X4 (LD)...............21
INSTALLATION - 4X2...................21
SPRING
REMOVAL.............................21
INSTALLATION.........................22
SHOCK
DIAGNOSIS AND TESTING - SHOCK........23
REMOVAL
REMOVAL - 4X2......................23
REMOVAL - 4X4......................23
INSTALLATION
INSTALLATION - 4X2...................23
INSTALLATION - 4X4...................23
STABILIZER BAR
DESCRIPTION.........................24
OPERATION...........................24
REMOVAL.............................24
INSTALLATION.........................24
STABILIZER LINK
REMOVAL
REMOVAL - 4X4......................24
REMOVAL - 4X2......................24
INSTALLATION
INSTALLATION - 4X4...................25
INSTALLATION - 4X2...................25
TORSION BAR
DESCRIPTION.........................25
OPERATION...........................25
REMOVAL.............................25
INSTALLATION.........................26
UPPER BALL JOINT
DIAGNOSIS AND TESTING - UPPER BALL
JOINT..............................26
UPPER CONTROL ARM
REMOVAL.............................27
INSTALLATION.........................27
2 - 8 FRONT - INDEPENDENT FRONT SUSPENSIONDR

FRONT - INDEPENDENT
FRONT SUSPENSION
DESCRIPTION
DESCRIPTION
The front suspension is designed to allow each
wheel to adapt to different road surfaces indepen-
dently. The wheels are mounted to hub/bearings
units bolted to the steering knuckle. The double-row
hub bearings are sealed and lubricated for life. The
steering knuckles turn (pivot) on ball joints.
The front suspension is comprised of (Fig. 1) (Fig. 2):
²Shock absorbers
²Torsion bar - 4X4 (LD only)
²Coil Spring - 4X2
²Control arms
²Steering knuckles
²Stabilizer bar
²Stabilizer link
²Tie Rod Ends
²Hub/Bearing
²Rack & Pinion
²Ball Joints
NOTE: Components attached with a nut must be
torqued to specification.
NOTE: Suspension components with rubber/ure-
thane bushings should be tightened with the vehi-
cle at normal ride height. It is important to have the
springs supporting the weight of the vehicle when
the fasteners are torqued. If springs are not at their
normal ride position, vehicle ride comfort could be
affected and premature bushing wear may occur.
DESCRIPTION
The upper control arm bolts on frame brackets.
The frame brackets have slotted holes which allow
the arms to be adjusted for caster and camber.
The lower control arms bolt to the lower frame
brackets and pivots through bushings.
The control arms have lube for life ball studs. The
control arm travel (jounce) is limited through the use
of rubber/urethane bumpers. Rebound travel is lim-
ited by the shock absorber.
Fig. 1 FRONT SUSPENSION - 4X2
1 - STABILIZER BAR
2 - UPPER CONTROL ARM
3 - STEERING KNUCKLE
4 - ROTOR
5 - CALIPER ADAPTER
6 - OUTER TIE ROD END
7 - STABILIZER LINK
8 - LOWER CONTROL ARM
9 - RACK & PINION
10 - COIL SPRING
11 - SHOCK ABSORBER
Fig. 2 FRONT SUSPENSION - 4X4 (LD ONLY)
1 - STABILIZER BAR
2 - UPPER CONTROL ARM
3 - STEERING KNUCKLE
4 - ROTOR
5 - OUTER TIE ROD END
6 - SHOCK ABSORBER
7 - STABILIZER LINK
8 - LOWER CONTROL ARM
9 - INNER TIE ROD
10 - RACK & PINION
DRFRONT - INDEPENDENT FRONT SUSPENSION 2 - 9

SPECIFICATIONS
TORQUE CHART
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Shock Absorber
Upper Nut
4X454 40 Ð
Shock Absorber
Lower Bolt
4X4135 100 Ð
Shock Absorber
Upper Nut
4X254 40 Ð
Shock Absorber
Lower Bolt
4X234 25 Ð
Lower Suspension Arm
Frame Nuts204 150 Ð
Lower Suspension Arm
Frame Nuts285 210 Ð
Lower Suspension Arm
Ball Joint Nut
1500 series only52
Then an additional 90É38
Then an additional 90ÉÐ
Lower Suspension Arm
Ball Joint Nut
(HD 4X2 only135 100 Ð
Upper Suspension Arm
Frame Nuts
(LD)132 97 Ð
Upper Suspension Arm
Frame Nuts
(HD 4X2 only)170 125 Ð
Upper Suspension Arm
Ball Joint Nut
1500 series only54
Then an additional 90É40
Then an additional 90ÉÐ
Stabilizer Bar
Frame Bolt61 45 Ð
Stabilizer Link
Lower Control Arm Nut102 75 Ð
Stabilizer Link
Stabilizer Bar Nut38 27 Ð
Hub/Bearing
Bolts
(LD)163 120 Ð
Hub/Bearing
Bolts
(HD 4X2)176 130 Ð
Tie Rod End
Nut61
Then an additional 90É45
Then an additional 90ÉÐ
2 - 10 FRONT - INDEPENDENT FRONT SUSPENSIONDR
FRONT - INDEPENDENT FRONT SUSPENSION (Continued)