wheel alignment JEEP GRAND CHEROKEE 2003 WJ / 2.G Workshop Manual

SUSPENSION
TABLE OF CONTENTS
page page
SUSPENSION
DIAGNOSIS AND TESTING - SUSPENSION
AND STEERING SYSTEM................1WHEEL ALIGNMENT......................3
FRONT.................................6
REAR.................................17
SUSPENSION
DIAGNOSIS AND TESTING - SUSPENSION AND
STEERING SYSTEM
CONDITION POSSIBLE CAUSES CORRECTION
FRONT END NOISE 1. Loose or worn wheel bearings. 1. Adjust or replace wheel bearings.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
EXCESSIVE PLAY IN
STEERING1. Loose or worn wheel bearings. 1. Adjust or replace wheel bearings.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Loose or worn steering gear. 3. Adjust or replace steering gear.
FRONT WHEELS SHIMMY 1. Loose or worn wheel bearings. 1. Adjust or replace wheel bearings.
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.
5. Leaking steering dampener. 5. Replace steering dampener.
VEHICLE INSTABILITY 1. Loose or worn wheel bearings. 1. Adjust or replace wheel bearings.
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.
EXCESSIVE STEERING
EFFORT1. Loose or worn steering gear. 1. Adjust or replace steering gear.
2. Power steering fluid low. 2. Add fluid and repair leak.
3. Column coupler binding. 3. Replace coupler.
4. Tire pressure. 4. Adjust tire pressure.
5. Alignment. 5. Align vehicle to specifications.
WJSUSPENSION 2 - 1

CONDITION POSSIBLE CAUSES CORRECTION
VEHICLE PULLS TO ONE
SIDE DURING BRAKING1. Uneven tire pressure. 1. Adjust tire pressure.
2. Worn brake components. 2. Repair brakes as necessary.
3. Air in brake line. 3. Repair as necessary.
VEHICLE LEADS OR
DRIFTS FROM STRAIGHT
AHEAD DIRECTION ON
UNCROWNED ROAD1. Radial tire lead. 1. Cross front tires.
2. Brakes dragging. 2. Repair brake as necessary.
3. Weak or broken spring. 3. Replace spring.
4. Uneven tire pressure. 4. Adjust tire pressure.
5. Wheel Alignment. 5. Align vehicle.
6. Loose or worn steering or
suspension components.6. Repair as necessary.
7. Cross caster out of spec. 7. Align vehicle.
KNOCKING, RATTLING
OR SQUEAKING1. Worn shock bushings. 1. Replace shock.
2. Loose, worn or bent steering/
suspension components.2. Inspect, tighten or replace components
as necessary.
3. Shock valve. 3. Replace shock.
IMPROPER TRACKING 1. Loose, worn or bent track bar. 1. Inspect, tighten or replace component as
necessary.
2. Loose, worn or bent steering/
suspension components.2. Inspect, tighten or replace components
as necessary.
2 - 2 SUSPENSIONWJ
SUSPENSION (Continued)

WHEEL ALIGNMENT
TABLE OF CONTENTS
page page
WHEEL ALIGNMENT
DESCRIPTION..........................3
OPERATION............................3
STANDARD PROCEDURE
STANDARD PROCEDURE - CAMBER.......3STANDARD PROCEDURE - CASTER.......4
STANDARD PROCEDURE - TOE POSITION . . 4
SPECIFICATIONS
ALIGNMENT..........................5
WHEEL ALIGNMENT
DESCRIPTION
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 position (Fig. 1).
CAUTION: Never attempt to modify suspension or
steering components by heating or bending.
CAUTION: Components attached with a nut and cot-
ter pin must be torqued to specification. Then if the
slot in the nut does not line up with the cotter pin
hole, tighten nut until it is aligned. Never loosen the
nut to align the cotter pin hole.
NOTE: Periodic lubrication of the front suspension/
steering system components may be required. Rub-
ber bushings must never be lubricated, Refer to
Lubrication And Maintenance for the recommended
maintenance schedule.
OPERATION
²CASTERis the forward or rearward tilt of the
steering knuckle from vertical. Tilting the top of the
knuckle rearward provides positive caster. Tilting the
top of the knuckle forward provides negative caster.
Caster is a directional stability angle. 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 theinside or outside edge of the tire. The angle is not
adjustable, damaged component(s) must be replaced
to correct the camber angle (Fig. 1).
²WHEEL TOE POSITIONis the difference
between the leading inside edges and trailing inside
edges of the front tires. Incorrect wheel toe position
is the most common cause of unstable steering and
uneven tire wear. The wheel toe position is thefinal
front wheel alignment adjustment (Fig. 1).
²STEERING AXIS INCLINATION ANGLEis
measured in degrees and is the angle that the steer-
ing knuckles are tilted. The inclination angle has a
fixed relationship with the camber angle. It will not
change except when a spindle or ball stud is dam-
aged or bent. The angle is not adjustable, damaged
component(s) must be replaced to correct the steering
axis inclination angle.
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).
STANDARD PROCEDURE
STANDARD PROCEDURE - CAMBER
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 three times. Always release the bumper in the
down position.
To obtain an accurate alignment, a 4 wheel align-
ment machine must be used and the equipment cali-
bration verified.
The wheel camber angle is preset. This angle is not
adjustable and cannot be altered.
WJWHEEL ALIGNMENT 2 - 3

STANDARD PROCEDURE - CASTER
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 three times. Always release the bumper in the
down position.
To obtain an accurate alignment, a 4 wheel align-
ment machine must be used and the equipment cali-
bration verified.
The wheel caster angle is preset. This angle is not
adjustable and cannot be altered.
STANDARD PROCEDURE - TOE POSITION
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 three times. Always release the bumper in the
down position.To obtain an accurate alignment, a 4 wheel align-
ment machine must be used and the equipment cali-
bration verified.
NOTE: For an accurate wheel toe position adjust-
ment the engine must be engine running.
(1) Apply parking brakes.
(2) Start the engine and turn wheels both ways
before straightening the steering wheel. Center and
secure the steering wheel.
(3) Loosen the tie rod adjustment sleeve clamp
bolts (Fig. 2).
(4) Turn the sleeve to obtain the preferred positive
TOE-IN specification. Position the clamp bolts as
shown (Fig. 2) for proper clearance.
(5) Tighten the clamp bolts to 68 N´m (50 ft. lbs.).
Fig. 1 Wheel Alignment Measurements
1 - WHEEL CENTERLINE
2 - NEGATIVE CAMBER ANGLE
3 - PIVOT CENTERLINE
4 - SCRUB RADIUS
5 - TRUE VERTICAL6 - KING PIN
7 - VERTICAL
8 - POSITIVE CASTER
2 - 4 WHEEL ALIGNMENTWJ
WHEEL ALIGNMENT (Continued)

NOTE: Make sure the toe setting does not change
during clamp tightening.
(6) Verify alignment specifications, then turn the
engine off.
STEERING WHEEL CENTERING
NOTE: The steering wheel can be centered without
affecting the toe position.
(1) Loosen the drag link adjustment sleeve clamp
bolts.
(2) Turn the adjustment sleeve to center the
wheel.
(3) Position the clamp bolts as shown (Fig. 2)for
proper clearance.
(4) Tighten the clamp bolts to 68 N´m (50 ft. lbs.).
(5) Road test the vehicle to verify the wheel is cen-
tered.
SPECIFICATIONS
ALIGNMENT
NOTE: Specifications are in degrees.
FRONT WHEELS - STANDARD SUSPENSION
SPECIFICATIONS
DESCRIPTION SPECIFICATION
PREFERRED CASTER
+ 6.75ÉCAMBER
20.37ÉTOTAL
TOE-IN
+ 0.20É
RANGE + 6.0É to
+ 7.5É20.75É
to + 0.5É+ .14É to
+ .26É
MAX RT/LT
DIFFERENCE0.5É 0.5É 0.5É
FRONT WHEELS - UP-COUNTRY SUSPENSION
SPECIFICATIONS
DESCRIPTION SPECIFICATION
PREFERRED CASTER
+ 6.5ÉCAMBER
20.37ÉTOTAL
TOE-IN
+ 0.20É
RANGE + 5.7É to
+ 7.2É20.75É
to+0É+ 0.0É to
+ .36É
MAX RT/LT
DIFFERENCE0.5É 0.5É 0.06É
REAR AXLE
SPECIFICATIONS
DESCRIPTION SPECIFICATION
PREFERRED CAMBER
±.37ÉTHRUST
ANGLE
0ÉTOTAL
TOE-IN
+.37É
RANGE 0É to
±.75É  0.25É 0É to
+.70É
Fig. 2 Steering Linkage
1 - DRAG LINK ADJUSTMENT SLEEVE
2 - TIE ROD ADJUSTMENT SLEEVE
WJWHEEL ALIGNMENT 2 - 5
WHEEL ALIGNMENT (Continued)

DIAGNOSIS AND TESTING - REAR
SUSPENSION
CONDITION POSSIBLE CAUSES CORRECTION
VEHICLE INSTABILITY 1. Loose or worn wheel bearings. 1. Replace wheel bearings.
2. Loose, worn or bent suspension
components.2. Inspect, tighten or replace components
as necessary.
3. Tire pressure. 3. Adjust tire pressure.
VEHICLE PULLS TO ONE
SIDE1. Weak or broken spring. 1. Replace spring.
2. Alignment. 2. Align vehicle to specifications.
3.Tires. 3. Replace tires.
4. Brakes. 4. Repair as necassary.
KNOCKING, RATTLING
OR SQUEAKING1. Worn shock bushings. 1. Replace shock.
2. Loose shock mounting. 2. Tighten to specifications.
3. Shock valve. 3. Replace shock.
4. Loose upper ball joint. 4. Replace ball joint.
5. Loose, worn or bent suspension
components.5. Inspect, tighten or replace components
as necessary.
IMPROPER TRACKING 1. Loose, worn or bent suspension
components.1. Inspect, tighten or replace components
as necessary.
2. Bent axle. 2.Replace axle.
SPECIFICATIONS
TORQUE CHART
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Shock Absorber Upper Nut 108 80 Ð
Shock Absorber Lower Nut 115 85 Ð
Suspension Arm Upper Ball Joint Nut 142 105 Ð
Suspension Arm Upper Frame Bolts 100 74 Ð
Ball Joint Plate Bolts 136 100 Ð
Suspension Arms Lower Axle Bracket Nut 163 120 Ð
Suspension Arms Lower Frame Bracket Nut 156 115 Ð
Stabilizer Bar Retainer Bolts 54 40 Ð
Stabilizer Bar Bar Link Nut 54 40 Ð
Stabilizer Bar Bracket Link Nut 92 68 Ð
2 - 18 REARWJ
REAR (Continued)

FRONT TUBE AXLE
TABLE OF CONTENTS
page page
FRONT TUBE AXLE
REMOVAL.............................14INSTALLATION.........................14
FRONT TUBE AXLE
REMOVAL
(1) Raise and support the vehicle.
(2) Position a lifting device under the axle and
secure axle to lift.
(3) Remove the wheels and tires.
(4) Remove the brake rotors (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/ROTORS - REMOVAL)
and calipers.
(5) Disconnect wheel sensor wiring harness from
the vehicle wiring harness.
(6) Remove stabilizer bar links at the axle.
(7) Remove shock absorbers from axle brackets.
(8) Removet track bar.
(9) Remove tie rod and drag link from the steering
knuckle.
(10) Remove steering damper from the axle
bracket.
(11) Remove upper and lower suspension arms
from the axle brackets.
(12) Lower the lift enough to remove the axle. The
coil springs will drop with the axle.
(13) Remove the coil springs from the axle.
INSTALLATION
CAUTION: The weight of the vehicle must be sup-
ported by the springs before suspension arms and
track bar fasteners are tightened. If not at their nor-mal ride position, ride height and handling could be
affected.
(1) Install springs and retainer clips and tighten
retainer bolts to 21 N´m (16 ft. lbs.).
(2) Lift and position axle under the vehicle and
align it with the spring pads.
(3) Position upper and lower suspension arms in
the axle brackets and loosely install bolts and nuts.
(4) Install track bar to the axle bracket and loosely
install bolt.
(5) Install shock absorbers and tighten bolts to 23
N´m (17 ft. lbs.).
(6) Install stabilizer bar links to the axle brackets
and tighten nuts to 95 N´m (70 ft. lbs.).
(7) Install drag link and tie rod to the steering
knuckles.
(8) Install steering damper to the axle bracket and
tighten nut to 75 N´m (55 ft. lbs.).
(9) Install the brake rotors and calipers.
(10) Connect wheel speed sensor wiring harness, if
equipped.
(11) Install the wheel and tire assemblies.
(12) Remove lift from the axle and lower the vehi-
cle.
(13) Tighten upper suspension arm nuts to 75 N´m
(55 ft. lbs.). Tighten lower suspension arm nuts to
115 N´m (85 ft. lbs.).
(14) Tighten track bar bolt at the axle bracket to
100 N´m (74 ft. lbs.).
(15) Check the front wheel alignment.
3 - 14 FRONT TUBE AXLEWJ

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.
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.
3 - 18 FRONT AXLE - 186FBIWJ
FRONT AXLE - 186FBI (Continued)

Condition Possible Causes Correction
Axle Noise 1. Insufficient lubricant. 1. Fill differential with the correct
fluid type and quantity.
2. Improper ring gear and pinion
adjustment.2. Check ring gear and pinion
contact pattern.
3. Unmatched ring gear and pinion. 3. Replace gears with a matched
ring gear and pinion.
4. Worn teeth on ring gear and/or
pinion.4. Replace ring gear and pinion.
5. Loose pinion bearings. 5. Adjust pinion bearing pre-load.
6. Loose differential bearings. 6. Adjust differential bearing
pre-load.
7. Mis-aligned or sprung ring gear. 7. Measure ring gear run-out.
Replace components as necessary.
8. Loose differential bearing cap
bolts.8. Inspect differential components
and replace as necessary. Ensure
that the bearing caps are torqued
tot he proper specification.
9. Housing not machined properly. 9. Replace housing.
VARI-LOKT
(1) Park the vehicle on a level surface or raise
vehicle on hoist so that the vehicle is level.
(2) Remove the axle fill plug.
(3) Verify that the axle fluid level is correct. The
fluid level is correct if the fluid is level with the bot-
tom of the fill hole.
(4) Shift the transfer case into the 4WD full-time
position.
(5) Drive the vehicle in a tight circle for 2 minutes
at 5mph to fully prime the pump.
(6) Block the tires opposite the axle to be tested to
prevent the vehicle from moving.
(7) Shift the transfer case into the 4WD Low posi-
tion and the transmission into the Park position.
(8) Raise both the wheels of the axle to be tested
off of the ground.
(9) Rotate the left wheel by hand at a minimum of
one revolution per second while an assistant rotates
the right wheel in the opposite direction.
(10) The left wheel should spin freely at first and
then increase in resistance within 5 revolutions until
the wheels cannot be continuously rotated in opposite
directions.
(11) The Vari-loktdifferential has engaged prop-
erly if the wheels cannot be rotated in opposite direc-
tions for a moment. After the wheels stop rotating for
a moment, the fluid pressure will drop in the differ-
ential and the wheels begin to rotate once again.
(12) If the system does not operate properly,
replace the Vari-loktdifferential.
REMOVAL
(1) Raise and support the vehicle.
(2) Position a suitable lifting device under the
axle.
(3) Secure axle to lift.
(4) Remove the wheels and tires.
(5) Remove the brake calipers and rotors (Refer to
5 - BRAKES/HYDRAULIC/MECHANICAL/ROTORS
- REMOVAL) from the axle.
(6) Disconnect the wheel sensor wiring harness
from the vehicle wiring harness.
(7) Disconnect the vent hose from the axle shaft
tube.
(8) Mark propeller shaft and yoke/pinion flange for
installation alignment reference.
(9) Remove propeller shaft.
(10) Disconnect stabilizer bar links at the axle.
(11) Disconnect shock absorbers from axle brack-
ets.
(12) Disconnect track bar.
(13) Disconnect the tie rod and drag link from the
steering knuckle.
(14) Disconnect the steering damper from the axle
bracket.
(15) Disconnect the upper and lower suspension
arms from the axle brackets.
(16) Lower the lifting device enough to remove the
axle. The coil springs will drop with the axle.
(17) Remove the coil springs from the axle.
3 - 20 FRONT AXLE - 186FBIWJ
FRONT AXLE - 186FBI (Continued)

INSTALLATION
CAUTION: The weight of the vehicle must be sup-
ported by the springs before suspension arms and
track bar fasteners can be tightened. If springs are
not at their normal ride position, ride height and
handling could be affected.
(1) Install the springs and retainer clips. Tighten
the retainer bolts to 21 N´m (16 ft. lbs.).
(2) Support the axle on a lifting device and posi-
tion axle under the vehicle.
(3) Raise the axle and align it with the spring
pads.
(4) Position the upper and lower suspension arms
in the axle brackets. Loosely install bolts and nuts to
hold suspension arms to the axle brackets.
(5) Install vent hose to the axle shaft tube.
(6) Install track bar in the axle bracket and install
the bolt loosely.
(7) Install shock absorbers and tighten the bolts to
23 N´m (17 ft. lbs.).
(8) Install stabilizer bar links to the axle brackets
and tighten the nuts to 95 N´m (70 ft. lbs.).
(9) Install drag link and tie rod to the steering
knuckles.
(10) Install steering damper to the axle bracket
and tighten the nut to 75 N´m (55 ft. lbs.).
(11) Install the brake rotors (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/ROTORS - INSTALLA-
TION) and calipers.
(12) Connect the wheel speed sensor wiring har-
ness to the vehicle wiring harness.
(13) Align the previously made marks on the pro-
peller shaft and the yoke/pinion flange.
(14) Install propeller shaft to pinion flange bolts ,
if equipped.
(15) Install propeller shaft to yoke straps and
bolts, if equipped.
(16) Check and fill axle lubricant.
(17) Install the wheel and tire assemblies.
(18) Remove the lifting device from the axle and
lower the vehicle.
(19) Tighten the upper suspension arm nuts to 75
N´m (55 ft. lbs.). Tighten the lower suspension arm
nuts to 115 N´m (85 ft. lbs.).
(20) Tighten the track bar bolt at the axle bracket
to 100 N´m (74 ft. lbs.).
(21) Check the front wheel alignment.
ADJUSTMENTS
Ring and pinion gears are supplied as matched
sets only. The identifying numbers for the ring and
pinion gear are etched onto each gear (Fig. 3). A plus
(+) number, minus (±) number or zero (0) is etched
into the face of the pinion gear. This number is theamount (in thousandths of an inch) the depth varies
from the standard depth setting of a pinion etched
with a (0). The standard setting from the center line
of the ring gear to the back face of the pinion is 92.1
mm (3.625 in.). The standard depth provides the best
gear tooth contact pattern. Refer to Backlash and
Contact Pattern Analysis paragraph in this section
for additional information.
Compensation for pinion depth variance is
achieved with a select shim/oil slinger. The shims are
placed between the rear pinion bearing and the pin-
ion gear head (Fig. 4).
Fig. 3 PINION GEAR ID NUMBERS
1 - PRODUCTION NUMBERS
2 - DRIVE PINION GEAR DEPTH VARIANCE
3 - GEAR MATCHING NUMBER
Fig. 4 ADJUSTMENT SHIM LOCATIONS
1 - PINION DEPTH SHIM/OIL SLINGER
2 - DIFFERENTIAL BEARING SHIM
3 - RING GEAR
4 - DIFFERENTIAL BEARING SHIM
5 - COLLAPSIBLE SPACER
WJFRONT AXLE - 186FBI 3 - 21
FRONT AXLE - 186FBI (Continued)