C 1500 Truck 2WD V8-5.3L VIN T (1999)
Alignment: Description and Operation
General Description
The front wheel alignment refers to the angular relationship between the front wheels, the front suspension attaching parts, and the ground. Proper
front wheel alignment must be maintained in order to ensure efficient steering, good directional stability, and prevent abnormal tire wear. The
following are the most important factors of the front wheel alignment:
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The camber
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The caster
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The toe-in
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The steering wheel pull
The caster is the tilting of the steering axis either forward or backward from vertical (1) when viewed from the side of the vehicle. A backward tilt is
measured in positive degrees (3) and a forward tilt in negative degrees (2).
On the short and the long arm type suspension, you cannot see a caster angle without a special instrument. However, if you look straight down from
the top of the upper control arm to the ground, the ball joints do not line up (fore and aft) when a caster angle other than 0 degrees is present. With a
positive angle, the lower ball joint center line will be slightly ahead (toward the front of the vehicle) of the upper ball joint center line. The caster is
designed into the front axle assembly on all vehicles, and is intended to be non-adjustable. However, you measure and find the caster to be out of
tolerance, the caster can be set to proper specifications.
The camber is the inward or the outward tilting of the front wheels from the vertical (2). When the wheels tilt outward at the top, the camber is positive
(3). When the wheels tilt inward at the top, the camber is negative. The amount of tilt measured in the degrees from the vertical is called the camber
angle.
If the camber is extreme or unequal between the wheels, improper steering and excessive tire wear will result. The negative camber causes wear of the
inboard side of the tire. The positive camber causes wear to the outboard side of the tire.
