Description and operation

Suspension components 4x4

DESCRIPTION

The front suspension is designed to allow each wheel to adapt to different road surfaces independently.

The wheels are mounted to hub/bearings units bolted to cast steering knuckle. The double-row hub bearings are sealed and lubricated for life. The steering knuckles turn (pivot) on ball joints. The upper ball joint is riveted to the outboard portion of the suspension arm and lubricated for life. The lower ball joint is pressed into the lower suspension arm and requires lubrication.

The front suspension is comprised of (Fig. 1):

• Shock absorbers
• Torsion-bar springs
• Suspension arms
• Steering knuckles
• Stabilizer bar

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/ 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.

Fig. 1 Front Suspension 4x4

1 - UPPER SUSPENSION ARM

2 - SHOCK ABSORBER

3 - STABILIZER BAR

4 - LOWER SUSPENSION ARM

5 - TORSION BAR

NOTE: Periodic lubrication of the front suspension/ steering system components may be required. Rubber bushings must never be lubricated. Refer to Group 0, Lubrication And Maintenance for the recommended maintenance schedule.

Shock absorbers

DESCRIPTION

The top of the low-pressure gas charged shock are bolted to the frame. The bottom of the shock are bolted to the lower suspension arm.

OPERATION

The shock absorbers dampen jounce and rebound of the vehicle over various road conditions.

Torsion bars

DESCRIPTION

The front of the bar mounts to the back side of the lower suspension arm. The rear end of the bar is mounted in a anchor that rests in the frame crossmember.

OPERATION

The torsion bars are used to control ride height and ride quality. The vehicle height is adjusted through an anchor adjustment bolt that increases or decreases the angle of the torsion bar. Increasing or decreasing the bar angle changes the angle of the suspension arms.

Steering knuckle

DESCRIPTION

The knuckle is a single casting with legs machined for the upper and lower ball joints. The knuckle also has machined mounting locations for the front brake calipers and hub bearing.

OPERATION

The steering knuckle pivot between the upper and lower ball joint. Steering linkage attached to the knuckle allows the vehicle to be steered.

Suspension arms

DESCRIPTION

The upper suspension arm bolts on frame brackets through the arm pivot shaft. The frame brackets have slotted holes which allow the arms to be adjusted for caster and camber. Pivot shaft bushings are not replaceable.

The lower suspension arms bolt to the lower frame brackets and pivot through bushings, these bushings are not replaceable.

The suspension arms have lube for life riveted ball studs. The suspension arm travel (jounce) is limited through the use of urethane bumpers. Rebound travel is limited by the shock absorber.

Stabilizer bar

DESCRIPTION

The bar extends across the front underside of the chassis and connects to the frame crossmember. The ends of the bar mount to the lower suspension arm.

All mounting points of the stabilizer bar are isolated by bushings.

OPERATION

The stabilizer bar is used to minimize vehicle front sway during turns. The bar helps to maintain a flat attitude to the road surface.