Toe-In
Linear sum toe-in results when the distance between the front wheels is less at the front of the axle than at the rear of the axle.Angular toe-in is the angle of the front wheel center-lines, relative to the intersection of the forward projected vehicle center line.
The actual amount of toe-in is normally a fraction of a degree. Toe-in is measured from the center of the tire treads or from the inboard side of the tires. The purpose of toe-in is to ensure parallel rolling of the front wheels and to offset any small deflections of the wheel support system which occur when the vehicle is rolling forward. Incorrect toe-in can cause unstable steering and front tire wear. Toe-in is the last angle to be set in the front wheel alignment procedure.