See Figures 1, 2, 3 and 4
Alignment should only be performed after it has been verified that all parts of the steering and suspension systems are in good operating condition. The truck must be empty. The tires must be cold and inflated to the correct pressure and the test surface must be level and horizontal.
Because special, elaborate equipment is required for proper front end alignment, it is recommended that the truck be taken to a reputable alignment shop.
Caster is the forward or rearward tilt of the upper end of the kingpin (1970-77), or the upper ball joint (1978-88), which results in a slight tilt of the steering axis forward or backward. Rearward tilt is referred to as positive caster, while forward tilt is referred to as negative caster.
Caster is adjusted by creating a difference in the total number (thickness) of shims, front and rear, between the upper control arm pivot shaft and its mounting bracket. Adjustment requires the use of special equipment.
Camber is the inward or outward tilt from the vertical, measured in degrees, of the front wheels at the top. An outward tilt gives the wheel positive camber. Proper camber is critical to assure even tire wear.
Camber is adjusted by adding or subtracting the same number and thickness of shims at the front and rear upper arm pivot shaft attaching bolts. Adjustment requires the use of special equipment.
Toe is the amount measured in a fraction of an inch, that the front wheels are closer together at one end than the other. Toe-in means that the front wheels are closer together at the front of the tire than at the rear; toe-out means that the rear of the tires are closer together than the front.
Although it is recommended that this adjustment be made by your dealer or a qualified shop, you can make it yourself if you make very careful measurement. The wheels must be dead straight ahead. The truck must have a full tank of gas, all fluids must be at their proper levels, all other suspension and steering adjustments must be correct and the tires must be properly inflated to their cold specification.
- Toe can be determined by measuring the distance between the centers of the tire treads, at the front of the tire and the rear. If the tread pattern of your truck's tires makes this impossible, you can measure between the edges of the wheel rims, but be sure to move the truck and measure in a few places to avoid errors caused by bent rims or wheel runout.
- If the measurement is not within specifications loosen the retaining clamp lock nuts on the adjustable tie rods.
- Turn the left and right tie rods EQUAL amounts until the measurements are within specifications.
- Tighten the lock bolts and then recheck the measurements. Check to see that the steering wheel is still in the proper position. If not, remove it and reposition it as detailed later in this section.
STEERING ANGLE ADJUSTMENT
The maximum steering angle is adjusted by stopper bolts located on the inside of the steering knuckle/spindle. Loosen the locknut on the stopper bolt, turn the stopper bolt, turn the stopper bolt in or out as required to obtain the proper maximum steering angle and retighten the locknut.