Toe In and Toe Out

The wheels of a car are designed to point inwards towards each other or outwards away from each other by a fraction of a degree. When the wheels are pointing towards each other Toe is positive and it is called Toe In. When the wheels are pointing outwards Toe is negative and it is called Toe Out. The purpose of Toe is to make sure that the wheels roll parallel to each other. When a car moves forward oncoming wind tries to force the wheels to point away from each other. This is why most normal road cars have Toe In. Once the car starts moving forward and wind tries to force them outwards the positive toe setting on the car is negated and the wheels point straight ahead. Soft rubber bushings at the suspension links aid toe movement. Different toe angles are used on race cars that are built for performance on different terrains.

Proper Toe angles reduce tyre wear while improper Toe angles on a car will result in premature tyre wear and steering instability. Toe angles are set by manufacturers of cars to minimise steering instability over uneven surfaces and to ensure that the wheels run parallel to each other.