Hummer H2. Manual — part 166

Fig. 3: Determining Camber Angle

CASTER

1. Caster is tilting of front steering axis either forward or backward from vertical, as viewed from side of

vehicle. See Fig. 4 .

2. When axis is tilted backward from vertical, caster is positive. This creates a trailing action on front

wheels. When axis is tilted forward, caster is negative, causing a leading action on front wheels.

1998 Chevrolet Pickup C1500

GENERAL INFORMATION Wheel Alignment Theory & Operation

Fig. 4: Determining Caster Angle

TOE-IN ADJUSTMENT

Toe-in is the width measured at the rear of the tires subtracted by the width measured at the front of the tires at
about spindle height. A positive figure would indicate toe-in and a negative figure would indicate toe-out. If the
distance between the front and rear of the tires is the same, toe measurement would be zero. To adjust:

1) Measure toe-in with front wheels in straight ahead position and steering wheel centered. To adjust toe-in,
loosen clamps and turn adjusting sleeve or adjustable end on right and left tie rods. See Fig. 2 and Fig. 5 .

2) Turn equally and in opposite directions to maintain steering wheel in centered position. Face of tie rod end
must be parallel with machined surface of steering rod end to prevent binding.

3) When tightening clamps, make certain that clamp bolts are positioned so there will be no interference with
other parts throughout the entire travel of linkage.

1998 Chevrolet Pickup C1500

GENERAL INFORMATION Wheel Alignment Theory & Operation

Fig. 5: Wheel Toe-In (Dimension A Less Dimension B)

TOE-OUT ON TURNS

1. Toe-out on turns (turning radius) is a check for bent or damaged parts, and not a service adjustment. With

caster, camber, and toe-in properly adjusted, check toe-out with weight of vehicle on wheels.

2. Use a full floating turntable under each wheel, repeating test with each wheel positioned for right and left

turns. Incorrect toe-out generally indicates a bent steering arm. Replace arm, if necessary, and recheck
wheel alignment.

STEERING AXIS INCLINATION

1. Steering axis inclination is a check for bent or damaged parts, and not a service adjustment. Vehicle must

be level and camber should be properly adjusted. See Fig. 6 .

2. If camber cannot be brought within limits and steering axis inclination is correct, steering knuckle is bent.

If camber and steering axis inclination are both incorrect by approximately the same amount, the upper
and lower control arms are bent.

1998 Chevrolet Pickup C1500

GENERAL INFORMATION Wheel Alignment Theory & Operation

Fig. 6: Checking Steering Axis Inclination

1998 Chevrolet Pickup C1500

GENERAL INFORMATION Wheel Alignment Theory & Operation