Jeep Cherokee (XJ): Rear suspension
Description and operation
Suspension component
The rear suspension is comprised of:
- Shock Absorbers
- Jounce Bumpers
- Stabilizer Bar (optional)
- Leaf Springs
- Drive Axle
CAUTION: A vehicle should always be loaded so the vehicle weight center-line is located immediately forward of the rear axle. Correct vehicle loading provides proper front tire-to-road contact. This results in maximum vehicle handling stability and safety. Incorrect vehicle weight distribution can cause excessive tire tread wear, spring fatigue or failure, and erratic steering.
CAUTION: Suspension components with rubber/ urethane bushings (except stabilizer bar) should be tightened with the vehicle 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.
Shock absorbers
DESCRIPTION
The top of the shock absorbers are bolted to the body crossmember. The bottom of the shocks are bolted to the axle brackets.
OPERATION
The shock absorbers dampen jounce and rebound motion of the vehicle over various road conditions and limit suspension rebound travel.
Jounce bumpers
DESCRIPTION
The jounce bumpers are bolted to the bottom of the frame rail.
OPERATION
The jounce bumpers are used to limit suspension travel in compression.
Stabilizer bar
DESCRIPTION
The spring steel bar extends across the axle and mounts to leaf spring brackets. Links are connected from the bar to the underside of the frame rail. The stabilizer bar and links are isolated by rubber bushings.
OPERATION
The stabilizer bar is used to control vehicle body roll during turns. The bar helps to control the vehicle body in relationship to the suspension.
Coil springs and isolators
DESCRIPTION
The front of the multi-leaf springs mount to frame rail brackets. The rear of the spring mounts to shackles which mount the frame. The springs and shackles have bushing at the mounting points.
OPERATION
The leaf springs control ride quality and maintain proper ride height. The shackles allow the springs to change their length as the vehicle moves over various road conditions. The bushings are used to isolate axle/road noise.
Diagnosis and testing
SPRING AND SHOCK
A knocking or rattling noise from a shock absorber may be caused by movement between mounting bushings and metal brackets or attaching components.
These noises can usually be stopped by tightening the attaching nuts. If the noise persists, inspect for damaged and worn bushings, and attaching 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 intermittent.
This condition is not repairable and the shock absorber must be replaced.
The shock absorbers are not refillable or adjustable.
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 spring eye and shock absorber bushings do not require any type of lubrication. Do not attempt to stop spring bushing noise by lubricating them.
Grease and mineral oil-base lubricants will deteriorate the bushing rubber.
If the vehicle is used for severe, off-road operation, the springs should be examined periodically. Check for broken and shifted leafs, loose and missing clips, and broken center bolts. Refer to Spring and Shock Absorber Diagnosis chart for additional information.
SPRING AND SHOCK ABSORBER
CONDITION |
POSSIBLE CAUSES |
CORRECTION |
SPRING SAGS |
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SPRING NOISE |
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SHOCK NOISE |
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Removal and installation
Shock absorber
REMOVAL
- Remove the shock absorber upper bolts from the body bracket (Fig. 1).
- Remove lower attaching nut and washer from the bracket stud. Remove the shock absorber.
INSTALLATION
- Install the shock absorber lower eye on the spring bracket stud. Install the shock absorber and upper bolts on the body bracket.
- Tighten the lower nut to 62 N·m (46 ft. lbs.).
- Tighten the upper bolts to 23 N·m (17 ft. lbs.).
Stabilizer bar
REMOVAL
- Raise and support the vehicle.
- Disconnect stabilizer bar links from spring brackets (Fig. 2).
- Disconnect the stabilizer bar brackets from the body rails. Remove the stabilizer bar and links.
INSTALLATION
- Position the stabilizer bar links at the spring brackets. Install the attaching bolts and nuts and tighten to 74 N·m (55 ft. lbs.).
- Attach the stabilizer bar to the body rail brackets with the bolts. Tighten to 54 N·m (40 ft. lbs.).
- Remove the supports and lower the vehicle.
REMOVAL AND INSTALLATION
Fig. 1 Rear Suspension Components
1 - SHOCK ABSORBER
2 - SPRING BRACKET
3 - NUT
4 - BUSHING
5 - BUMPER
6 - BRACKET
7 - NUT
8 - RETAINER
9 - SHOCK ABSORBER
10 - SPRING
11 - U-BOLTS
12 - BUSHING
13 - SHACKLE
Leaf spring
REMOVAL
- Raise vehicle at body rails.
- Remove the wheel and tire assemblies.
- Support axle with hydraulic jack to relieve axle weight.
- Disconnect the stabilizer bar link from the spring bracket stud.
- Remove nuts, U-bolts and spring bracket from axle.
- Remove nut and bolt attaching spring front eye to shackle.
- Remove nut and bolt from spring rear eye.
- Remove spring from vehicle.
INSTALLATION
- Position the spring front eye in the bracket. Loosely install the attaching bolt and nut. Do not tighten at this time.
- Position the rear eye in the shackle bracket. Loosely install the attaching bolt and nut. Do not tighten at this time.
- Position the axle. Install the spring bracket, U-bolts and nuts. Tighten the nuts to 70 N·m (52 ft. lbs.).
- Connect the stabilizer bar link to the spring bracket.
- Remove the hydraulic jack.
- Lower the vehicle.
- Tighten the spring front eye attaching bolts to 156 N·m (115 ft. lbs.).
- Tighten the spring rear eye attaching bolts to 108 N·m (80 ft. lbs.).
- Tighten the stabilizer bar link to 74 N·m (55 ft. lbs.).
Leaf spring and shackle bushing
For front bushings bend tabs DOWN before removal. Use an appropriate driver tool and force the original bushing out of the spring eye.
Fig. 2 Stabilizer Bar
1 - LINK
2 - BUSHING
3 - GROMMET
4 - FRAME RAIL
5 - CLAMP
6 - SCREW
7 - NUT
8 - SPRING BRACKET
9 - BOLT
10 - SWAY BAR
11 - SCREW
- Assemble tools shown (Fig. 3). Tighten nut at the socket wrench end of the threaded rod until the bushing is forced out.
- Assemble and align the bushing installation tools.
- Align the bushing with the spring eye or shackle eye and tighten the nut at the socket wrench end of the threaded rod. Tighten until the bushing is forced into the spring eye. NOTE: 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.
- For front bushings bend tabs up after installation.
Fig. 3 Spring Eye Bushing Removal
1 - NUT
2 - PIPE
(RECEIVER)
3 - SPRING EYE
4 - NUT
5 - THREADED ROD
6 - FLAT WASHER
7 - SOCKET WRENCH
(DRIVER)
Specifications
TORQUE CHART
DESCRIPTION TORQUE
Shock Absorber
Upper Bolt . . . . . . . . . . . . . . . 23 N·m (17 ft. lbs.)
Lower Nut . . . . . . . . . . . . . . . 62 N·m (46 ft. lbs.)
Stabilizer Bar
Clamp Bolt . . . . . . . . . . . . . . . 54 N·m (40 ft. lbs.)
Link Upper Bolt . . . . . . . . . . . 12 N·m (9 ft. lbs.)
Link Lower Nut . . . . . . . . . . . 74 N·m (55 ft. lbs.)
Spring
U-Bolt Nut . . . . . . . . . . . . . . . 70 N·m (52 ft. lbs.)
Front Pivot Bolt . . . . . . . . . 156 N·m (115 ft. lbs.)
Upper Shackle Bolt . . . . . . 156 N·m (115 ft. lbs.)
Lower Shackle Bolt . . . . . . . 108 N·m (80 ft. lbs.)
Other materials:
Tire Pressure. Tire Inflation Pressures. Tire Pressures For High Speed Operation
Tire Pressure
Proper tire inflation pressure is essential to the safe and
satisfactory operation of your vehicle. Four primary areas
are affected by improper tire pressure:
Safety and Vehicle Stability
Economy
Tread Wear
Ride Comfort
Safety
WARNING!
Improperly inflated tires are ...