Jeep 1997 Grand Cherokee Service Manual page 31

ZG
DESCRIPTION AND OPERATION (Continued)
replaceable ball studs attached to the axle tube
yokes.
Shock Absorbers: The shock absorbers dampen
jounce and rebound motion of the vehicle over vari-
ous road conditions. The top of the shock absorbers
are bolted to the body. The bottom of the shocks are
bolted to the axle brackets.
Coil Springs: The coil springs control ride quality
and maintain proper ride height. The coil springs
mount up in the wheelhouse which is part of the
unitized body bracket. A rubber doughnut isolator is
located between the top of the spring and the body.
The bottom of the spring seats on a axle pad and is
retained with a clip.
Upper And Lower Suspension Arms: The sus-
pension arms use bushings to isolate road noise. The
suspension arms are bolted to the frame and axle
through the rubber bushings. The lower suspension
arm uses cam bolts at the axle to allow for caster
and pinion angle adjustment. The suspension arm
travel is limited through the use of jounce bumpers
in compression and shocks absorbers in rebound.
Stabilizer Bar: The stabilizer bar is used to con-
trol vehicle body roll during turns. The spring steel
bar helps to control the vehicle body in relationship
to the suspension. The bar extends across the front
underside of the chassis and connects to the frame
rails. Links are connected from the bar to the axle
brackets. Stabilizer bar mounts are isolated by rub-
ber bushings.
Track Bar: The track bar is used to control front
axle lateral movement. The bar is attached to a
frame rail bracket with a ball stud and isolated with
a bushing at the axle bracket.
CAUTION: Components attached with a nut and
cotter 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.
CAUTION: Suspension components with rubber
bushings (except stabilizer bar) should be tightened
with the vehicle at normal ride height. It is impor-
tant 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 bush-
ing wear may occur. Rubber bushings must never
be lubricated.
NOTE: Periodic lubrication of the front suspension
(steering) system components is required. Refer to
Group 0, Lubrication And Maintenance for the rec-
ommended maintenance schedule.
DIAGNOSIS AND TESTING
SHOCK DIAGNOSIS
A knocking or rattling noise from a shock absorber
may be caused by movement between mounting
bushings and metal brackets or attaching compo-
nents. These noises can usually be stopped by tight-
ening the attaching nuts. If the noise persists,
inspect for damaged and worn bushings, and attach-
ing components. Repair as necessary if any of these
conditions exist.
A squeaking noise from the shock absorber may be
caused by the hydraulic valving and may be intermit-
tent. This condition is not repairable and the shock
absorber must be replaced.
The shock absorbers are not refillable or adjust-
able. If a malfunction occurs, the shock absorber
must be replaced. To test a shock absorber, hold it in
an upright position and force the piston in and out of
the cylinder four or five times. The action throughout
each stroke should be smooth and even.
The shock absorber bushings do not require any
type of lubrication. Do not attempt to stop bushing
noise by lubricating them. Grease and mineral oil-
base lubricants will deteriorate the bushing.
REMOVAL AND INSTALLATION
SHOCK ABSORBER
REMOVAL
(1) Remove the nut, retainer and grommet from
the upper stud in the engine compartment (Fig. 2).
(2) Remove the lower nuts and bolts from the axle
bracket. Remove the shock absorber.
INSTALLATION
(1) Position the lower retainer and grommet on the
upper stud. Insert the shock absorber through the
shock tower hole.
(2) Install the lower bolts and nuts. Tighten nuts
to 28 N·m (250 in. lbs.).
(3) Install the upper grommet and retainer on the
stud in the engine compartment. Install the nut and
tighten to 23 N·m (17 ft. lbs.).
COIL SPRING
REMOVAL
(1) Raise and support the vehicle. Position a
hydraulic jack under the axle to support it.
(2) Remove rear lower suspension arm bolts.
(3) Remove caliper flex hose brackets from the
frame rails.
(4) Remove ABS sensor wires from brackets.
SUSPENSION 2 - 5