Only caster, camber, and toe-in settings are adjustable. Specifications for steering axis inclination and wheel pivot ratio are useful only in detecting damaged components. Caster and camber cannot be set accurately without professional equipment. Toe-in can be adjusted with some degree of success without any special equipment. Front end height should be checked before adjusting front end alignment.
Caster is the backward or forward tilt from the vertical of the steering knuckle centerline at the top, measured in degrees. A steering knuckle centerline tilted backward at the top has positive (+) caster, while one tilted forward has negative (-) caster. Most American cars have negative or zero caster to reduce steering effort. Positive caster produces greater directional stability and requires greater steering effort, since it also increases the self-centering effect at the steering wheel.
Caster is adjusted by loosening either one of the upper control arm pivot bar adjusting bolts and moving the pivot bar. The bolts should be tightened to 150 ft. lbs. after adjustment.
Camber is the inward or outward tilt, measured in degrees, of the wheel at the top. A wheel tilted out at the top has positive (+) camber. A wheel tilted in has negative (-) camber. Camber has a great effect on tire wear.
Camber is adjusted by loosening both the upper control arm pivot bar adjusting bolts and moving both ends of the pivot bar equal amounts. The bolts should be tightened to 150 ft. lbs. after adjustment. Caster should always be rechecked after setting camber.
Toe-in is the amount, measured in inches, that the centerlines of the wheels are closer together at the front than at the rear. Virtually all cars, except some with front wheel drive, are set with toe-in. Front wheel drive cars usually require toe-out to prevent excessive toe-in under power.
Toe-in must be checked after caster and camber have been adjusted, but it can be adjusted without checking the other two settings.
Toe-in is adjusted at the tie-rod sleeves. The wheels must be straight-ahead when adjusting toe-in.
- Loosen the clamp bolts on the tie-rod sleeves.
- Rotate the sleeves equally (in opposite directions) to obtain the correct measurement. If the sleeves are not adjusted equally, the steering wheel will be crooked.
If your steering wheel is already crooked, it can be straightened by turning the sleeves equally in the same direction.
- Toe-in can be determined by measuring the distance between the centers of the tire treads, front and rear.
- When the adjustment is complete, turn the U of the clamps down and tighten the bolts to 11 ft. lbs. A torque wrench isn't essential here, but don't overtighten the clamps.