I have a 98 f150 that I recently put new lower ball joints, upper control arms and new tires on.I aligned the front end with a string line and a tape measure.The measurments are the same front and back of the front tires center point, 65 1/2 inch.The string line has the front tires aligned with the back tires.When I drive the truck it pulls a little to the right,am I correct to assume some toe in would alleviate this pull?If so what is allowable without tire wear and what would the toe in measurement be in inches not degrees?

 

i set a cement block on the outside of each front tire. Lay a straight 2 x 4 on the block so it sticks out a foot in front of the tire, and a foot behind the tire (front tires), 8 inches off the ground. Push the 2 x 4 up against the tire snug and measure the distance from left to right outside the 2 x 4 an inch in front of the tire and an inch behind the tire. YOu should have about 1/8 inch toe in. As you drive the tires will suck in a little more than that....... When you think you have it real close, roll the truck backward a couple feet, then pull forward a few feet and stop without moving the steering wheel. Do the block thing again and verify.. 1/8 inch is not a big number and easy to get bad measureemnts if tire is warped or your setting on the white letters, etc. When you get a couple consecutive good numbers, your done.

 

the other thing you want to do is find a flat level drive way and run a partial camber/caster test. The ground has to be LEVEL side to side where the tires set. Point the tires straight forward, then take a 30 inch level and lay against the tire vertical, just behind the center of axle. Dont get on the bottom tire bulge. Pull the top of the level out slightly untill the bubble is centered. You should have a 3/16 or 1/4 inch gap between the level and the tire at the top. Do this on both sides. If you are more vertical than that, you need to push the upper A-frame in to compensate.

 

we dont have a good way to measure caster at home..

Camber

The most widely discussed and controversial of the three elements is camber. Camber angle is the measure in degrees of the difference between the wheels vertical alignment perpendicular to the surface. If a wheel is perfectly perpendicular to the surface, its camber would be 0 degrees. Camber is described as negative when the top of the tires begin to tilt inward towards the fender wells. Consequently, when the top of the tires begin to tilt away from the vehicle it is considered positive.
Negative camber is becoming increasingly more popular because of its visual appeal. The real advantages to negative camber are seen in the handling characteristics. An aggressive driver will enjoy the benefits of increased grip during heavy cornering with negative camber. During straight acceleration however, negative camber will reduce the contact surface between the tires and road surface.