front axle JEEP GRAND CHEROKEE 2002 WJ / 2.G User Guide

LOWER BALL JOINT
REMOVAL
Ball stud service procedures below require removal
of the hub bearing and axle shaft. Removal and
installation of upper and lower ball studs require the
use of Tool Kit 6289.
(1) Position tools as shown to remove and install
ball stud (Fig. 6).
LOWER CONTROL ARM
DESCRIPTION
The lower suspension arms are hydroformed steel
and use voided oval bushings at one end of the arm.
OPERATION
The bushings provide isolation from the axle. The
arms mount to the unibody frame rail bracket and
the axle brackets. The arm and bushings provide
location and react to loads from the axle.
REMOVAL
(1) Raise the vehicle and support the front axle.
(2) Remove the lower suspension arm nut and bolt
from the axle bracket (Fig. 7).
(3) Remove the nut and bolt from the frame rail
bracket and remove the lower suspension arm (Fig.
7).
INSTALLATION
(1) Position the lower suspension arm in the axle
bracket and frame rail bracket.
NOTE: The end of the arm with the oval bushing
attaches to the axle bracket.
(2) Install the axle bracket bolt and nut finger
tight.
(3) Install the frame rail bracket bolt and nut fin-
ger tight.
(4) Remove support and lower the vehicle.
(5) With the vehicle on the ground tighten the
frame bracket bolt to 156 N´m (115 ft. lbs.). Tighten
the axle bracket nut to 163 N´m (120 ft. lbs.).
(6) Check the alignment if new parts were
installed.
Fig. 6 Lower
1 - SPECIAL TOOL 6289±12
2 - SPECIAL TOOL 6289±4
3 - SPECIAL TOOL 4212F
4 - SPECIAL TOOL 4212F5 - SPECIAL TOOL 6289±1
6 - SPECIAL TOOL 6289±3
WJFRONT 2 - 11

SHOCK
DESCRIPTION
The top of the shock absorbers are bolted to the
body. The bottom of the shocks are bolted to the axle
brackets. The standard shocks have conventional
twin tube construction and are low pressure gas
charged. Gas charging prevents cavitation during
rough road operation. Up-Country shocks are mono
tube design and are high pressure gas charged.
OPERATION
The shock absorbers dampen jounce and rebound
motion of the vehicle over various road conditions
and limit suspension rebound travel.
REMOVAL
(1) Remove the nut, retainer and grommet from
the shock stud in the engine compartment (Fig. 8).
(2) Raise and support the front axle.
(3) Remove the lower mounting nuts from the axle
bracket (Fig. 9). Remove the shock absorber.
INSTALLATION
(1) Position the lower retainer and grommet on the
shock stud. Insert the shock absorber through the
shock tower hole.
(2) Install the lower shock studs into the axle
bracket.
(3) Install the mounting nuts and tighten to 28
N´m (250 in. lbs.).
(4) Remove support and lower the vehicle.(5) Install the upper grommet, retainer and nut on
the stud in the engine compartment. Hold the shock
stud witha8mmwrench and tighten the nut to 35
N´m (26 ft. lbs.).SPRING
DESCRIPTION
The coil springs mount up in the wheelhouse which
is part of the unitized body bracket. A rubber dough-
nut isolator is located between the top of the spring
and the body. The bottom of the spring seats on a
axle isolator made of rubber with a steel insert.
Fig. 7 Lower Suspension Arm
1 - LOWER SUSPENSION ARM
2 - FRAME RAIL BRACKET
3 - AXLE BRACKET
Fig. 8 Upper Shock Mounting
1 - RETAINER
2 - STUD
3 - NUT
4 - GROMMET
Fig. 9 Lower Shock Mounting
1 - SHOCK ABSORBER
2 - MOUNTING NUTS
2 - 12 FRONTWJ
LOWER CONTROL ARM (Continued)

OPERATION
The coil springs control ride quality and maintain
proper ride height. The isolators provide road noise
isolation.
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the wheel and tire assemblies.
(3) Position a hydraulic jack under the axle to sup-
port it.
(4) Remove shock absorbers lower mounting nuts
from the axle brackets.
(5) Remove the track bar mounting bolt from the
axle bracket.
NOTE: Make sure the lower part of the shock does
not hold tension on the brake lines at the axle tube
housing located at the lower shock mounting area.
(6) Lower the axle until the spring is free from the
upper mount and isolator (Fig. 10).
(7) Remove the spring from the vehicle.
(8) Remove and inspect the upper and lower
spring isolators.
INSTALLATION
(1) Install the upper isolator.
(2) Install the lower isolator with the isolator loca-
tor nub in the axle pad hole (Fig. 11).
(3) Position the coil spring on the axle spring pad.CAUTION: Ensure the spring is positioned on the
lower isolator with the end of the spring coil
against the isolator spring locator (Fig. 12).
(4) Raise the axle and guide the springs onto the
spring upper mounts and lower shock studs into the
axle brackets.
(5) Install the shock absorbers lower mounting
nuts.
Fig. 10 Front Coil Spring
1 - UPPER ISOLATOR
2 - COIL SPRING
3 - LOWER ISOLATOR
4 - STABILIZER LINK
Fig. 11 Lower Isolator
1 - LOCATING NUB
2 - LOWER ISOLATOR
3 - AXLE SPRING PAD
4 - LOCATING HOLE
Fig. 12 Isolator Spring Locator
1 - COIL SPRING
2 - SPRING LOCATOR
3 - LOWER ISOLATOR
WJFRONT 2 - 13
SPRING (Continued)

(6) Install the track bar to the axle bracket and
install the mounting bolt.
NOTE: It may be necessary to pry the axle assem-
bly over to install the track bar bolt.
(7) Remove the hydraulic jack from under the
vehicle.
(8) Tighten all suspension components to proper
torque.
(9) Install the wheel and tire assemblies.
(10) Remove support and lower vehicle.
STABILIZER BAR
DESCRIPTION
The bar extends across the front underside of the
chassis and is mounted to the frame rails. Links are
connected from the bar to the axle brackets. The sta-
bilizer bar and links are isolated by rubber bushings.
OPERATION
The stabilizer bar is used to control vehicle body
roll during turns. The spring steel bar helps to con-
trol the vehicle body in relationship to the suspen-
sion.
REMOVAL
(1) Raise and support the vehicle.
(2) Remove link nuts and bolts (Fig. 13) and
remove the links.
(3) Remove the stabilizer bar retainer bolts (Fig.
13)from the frame rails and remove the stabilizer
bar.
INSTALLATION
(1) Position the stabilizer bar on the frame rail
and install the retainers and bolts. Ensure the bar is
centered with equal spacing on both sides. Tighten
the bolts to 92 N´m (68 ft. lbs.).
(2) Install the links onto the stabilizer bar and
axle brackets and install the bolts and nuts finger
tight.
(3) Remove the supports and lower the vehicle.
(4) With the vehicle on the ground tighten the sta-
bilizer bar link nuts to 106 N´m (78 ft. lbs.).
TRACK BAR
DESCRIPTION
The bar is attached to a frame rail bracket and
axle bracket. The bar is forged and has non replace-
able isolator bushings at both ends.
OPERATION
The track bar is used to control front axle lateral
movement and provides cross car location of the axle
assembly.
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the nut and bolt from the frame rail
bracket (Fig. 14).
(3) Remove the bolt from the axle shaft tube
bracket (Fig. 15). Remove the track bar.
INSTALLATION
(1) Install the track bar to the axle tube bracket.
Install the retaining bolt finger tight.
Fig. 13 Stabilizer Bar
1 - LINK
2 - STABILIZER BAR
3 - BUSHING
4 - RETAINER
Fig. 14 Track Bar Frame Rail Bracket
1 - FRAME RAIL
2 - TRACK BAR
2 - 14 FRONTWJ
SPRING (Continued)

(2) Install track bar to the frame rail bracket.
Install the bolt and nut finger tight.NOTE: It may be necessary to pry the axle assem-
bly over to install the track bar to the frame rail
bracket.
(3) Remove the supports and lower the vehicle.
(4) With the vehicle on the ground tighten the nut
at the frame rail bracket and to the bolt at the axle
bracket to 100 N´m (74 ft. lbs.).
(5) Check alignment specifications if a new track
bar was installed.
UPPER BALL JOINT
REMOVAL
Ball stud service procedures below require removal
of the hub bearing and axle shaft. Removal and
installation of upper and lower ball studs require the
use of Tool Kit 6289.
(1) Position tools as shown to remove and install
ball stud (Fig. 16).
Fig. 16 Upper
Fig. 15 Track Bar Axle Bracket
1 - AXLE BRACKET
2 - TRACK BAR
WJFRONT 2 - 15
TRACK BAR (Continued)

UPPER CONTROL ARM
DESCRIPTION
The upper suspension arms are hydroformed steel
and use rubber bushings at each end of the arm.
OPERATION
The arms mount to the unibody frame rail bracket
and the axle brackets. The arm and bushings provide
location and react to loads from the axle. The bush-
ings provide isolation from the axle.
REMOVAL
(1) Raise vehicle and support the axle.
(2) Remove the upper suspension arm mounting
nut and bolt (Fig. 17) from the axle bracket.(3) Remove the nut and bolt (Fig. 17) at the frame
rail and remove the upper suspension arm.
INSTALLATION
(1) Position the upper suspension arm at the axle
and frame rail.
(2) Install the bolts and finger tighten the nuts.
(3) Remove the supports and lower the vehicle.
(4) With the vehicle on the ground tighten the axle
bracket nut and the frame bracket bolt to 61 N´m (45
ft. lbs.).
(5) Check the alignment if new parts were
installed.
Fig. 17 Upper Suspension Arm
1 - UPPER SUSPENSION ARM
2 - FRAME BOLT
3 - AXLE BOLT
2 - 16 FRONTWJ

DIFFERENTIAL & DRIVELINE
TABLE OF CONTENTS
page page
PROPELLER SHAFT......................1
FRONT TUBE AXLE......................14
FRONT AXLE - 186FBI....................15REAR AXLE - 198RBI.....................50
REAR AXLE - 226RBA....................90
PROPELLER SHAFT
TABLE OF CONTENTS
page page
PROPELLER SHAFT
DIAGNOSIS AND TESTING................1
STANDARD PROCEDURES................3
SPECIFICATIONS........................5
SPECIAL TOOLS........................5
PROPELLER SHAFT - FRONT
REMOVAL.............................6
INSTALLATION..........................6
PROPELLER SHAFT - FRONT 4.7L
REMOVAL.............................6INSTALLATION..........................7
PROPELLER SHAFT - REAR
REMOVAL.............................7
INSTALLATION..........................7
SINGLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY..........................8
ASSEMBLY.............................9
DOUBLE CARDAN UNIVERSAL JOINTS
DISASSEMBLY..........................9
ASSEMBLY............................10
PROPELLER SHAFT
DIAGNOSIS AND TESTING
VIBRATION
Tires that are out-of-round, or wheels that are
unbalanced, will cause a low frequency vibration.
(Refer to 22 - TIRES/WHEELS - DIAGNOSIS AND
TESTING)
Brake rotors that are unbalanced will cause a
harsh, low frequency vibration. (Refer to 5 - BRAKES
- DIAGNOSIS AND TESTING)Driveline vibration can also result from loose or
damaged engine mounts.
Propeller shaft vibration increases as the vehicle
speed is increased. A vibration that occurs within a
specific speed range is not usually caused by a pro-
peller shaft being unbalanced. Defective universal
joints, or an incorrect propeller shaft angle, are usu-
ally the cause of such a vibration.
WJDIFFERENTIAL & DRIVELINE 3 - 1

(10) Start the engine and re-check for vibration. If
there is little or no change in vibration, move the
clamp to one of the other three positions. Repeat the
vibration test.
(11) If there is no difference in vibration at the
other positions, the source of the vibration may not
be propeller shaft.
(12) If the vibration decreased, install a second
clamp (Fig. 2) and repeat the test.
(13) If the additional clamp causes an additional
vibration, separate the clamps (1/4 inch above and
below the mark). Repeat the vibration test (Fig. 3).
(14) Increase distance between the clamp screws
and repeat the test until the amount of vibration is
at the lowest level. Bend the slack end of the clamps
so the screws will not loosen.
(15) If the vibration remains unacceptable, apply
the same steps to the front end of the propeller shaft.
(16) Install the wheel and tires. Lower the vehicle.RUNOUT
(1) Remove dirt, rust, paint, and undercoating
from the propeller shaft surface where the dial indi-
cator will contact the shaft.
(2) The dial indicator must be installed perpendic-
ular to the shaft surface.
(3) Measure runout at the center and ends of the
shaft sufficiently far away from weld areas to ensure
that the effects of the weld process will not enter into
the measurements.
(4) Refer to Runout Specifications chart.
(5) If the propeller shaft runout is out of specifica-
tion, remove the propeller shaft, index the shaft 180É,
and re-install the propeller shaft. Measure shaft
runout again.
(6) If the propeller shaft runout is now within
specifications, mark the shaft and yokes for proper
orientation.
(7) If the propeller shaft runout is not within spec-
ifications, verify that the runout of the transmission/
transfer case and axle are within specifications.
Correct as necessary and re-measure propeller shaft
runout.
(8) Replace the propeller shaft if the runout still
exceeds the limits.
RUNOUT SPECIFICATIONS
Front of Shaft 0.020 in. (0.50 mm)
Center of Shaft 0.025 in. (0.63 mm)
Rear of Shaft 0.020 in. (0.50 mm)
note:
Measure front/rear runout approximately 3 inches (76
mm) from the weld seam at each end of the shaft
tube for tube lengths over 30 inches. For tube lengths
under 30 inches, the maximum allowed runout is
0.020 in. (0.50 mm) for the full length of the tube.
STANDARD PROCEDURES
This procedure applies to both the front propeller
shafts and the rear propeller shaft. To obtain the
front (output) angle on the C/V front propeller shaft,
the inclinometer is placed on the machined ring of
the pinion flange. To obtain the propeller shaft angle
measurement on the C/V front propeller shaft, the
inclinometer is placed on the propeller shaft tube.
PROPELLER SHAFT ANGLE
(1) Raise and support the vehicle at the axles as
level as possible. Allow the wheels and propeller
shaft to turn.
(2) Remove any external bearing snap rings from
universal joint if equipped, so the inclinometer base
will sits flat.
Fig. 2 TWO CLAMP SCREWS
Fig. 3 CLAMP SCREWS SEPARATED
1 - ó INCH
WJPROPELLER SHAFT 3 - 3
PROPELLER SHAFT (Continued)

(3) Rotate the shaft until transmission/transfer
case output yoke bearing cap is facing downward, if
necessary.
NOTE: Always make measurements from front to rear.
(4)Place Inclinometer on yoke bearing cap, or the
pinion flange ring, (A) parallel to the shaft (Fig. 4). Cen-
ter bubble in sight glass and record measurement.
NOTE: This measurement will give you the trans-
mission or Output Yoke Angle (A).
(5) Rotate propeller shaft 90 degrees and place
Inclinometer on yoke bearing cap, or propeller shaft
tube on C/V propeller shaft, parallel to the shaft (Fig.
5). Center bubble in sight glass and record measure-
ment. This measurement can also be taken at the
rear end of the shaft.
NOTE: This measurement will give you the propeller
shaft angle (C).
(6) Subtract smaller figure from larger (C minus
A) to obtain transmission output operating angle.
(7) Rotate propeller shaft 90 degrees and place
Inclinometer on pinion yoke bearing cap parallel to
the shaft (Fig. 6). Center bubble in sight glass and
record measurement.
NOTE: This measurement will give you the pinion
shaft or input yoke angle (B).
(8) Subtract smaller figure from larger (C minus
B) to obtain axle Input Operating Angle.Refer to rules given below and the example in (Fig.
7) for additional information.
²Good cancellation of U-joint operating angles
(within 1É).
²Operating angles less than 3É.
²Operating angles less than 10É for double cardan
U-joint.
²At least 1/2 of one degree continuous operating
(propeller shaft) angle.
Fig. 4 OUTPUT YOKE ANGLE (A)
1 - SLIP YOKE BEARING CAP
2 - INCLINOMETER
Fig. 5 PROPELLER SHAFT ANGLE (C)
1 - SHAFT YOKE BEARING CAP
2 - INCLINOMETER
Fig. 6 INPUT YOKE ANGLE (B)
1 - PINION YOKE BEARING CAP
2 - INCLINOMETER
3 - 4 PROPELLER SHAFTWJ
PROPELLER SHAFT (Continued)

SPECIFICATIONS
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Front Shaft - Companion Flange Bolts 32 24 -
4.7L Front Shaft - Axle Yoke Nuts 19 14 -
4.7L Front Shaft - Transfer Case Bolts 27 20 -
Rear Shaft - Yoke Nuts 19 14 -
SPECIAL TOOLS
Fig. 7 U-JOINT ANGLE EXAMPLE
1 - 4.9É Angle (C)
2 - 3.2É Angle (B)
3 - Input Yoke4 - 3.0É Angle (A)
5 - Output Yoke
Inclinometer 7663
WJPROPELLER SHAFT 3 - 5
PROPELLER SHAFT (Continued)