For maximum benefits to tyre life and even wear, your alignment settings should be set as close to zero as the vehicle manufacturer’s tolerances allow.
Camber refers to the vertical angle, or tilt of the wheel in relation to the car when viewed from the front or rear. The amount of camber isn’t always noticeable to the eye but if the top of the wheel leans away from the car, this is described as positive camber. If the top of the wheel leans in at the top, this is negative camber. Correctly adjusted camber is important otherwise tyre wear will be increased and the vehicle’s handling could be compromised.
The toe angle refers to the direction of the wheels in relation to the centre line of the vehicle when viewed from above. Imagine the wheels as a pair of feet. If the toes point inwards, this is described as toe-in whereas if your heel point together, this is described as toe-out. If your car suffers from toe-in, you will suffer from excessive wear on the outside edges of your tyres whereas toe-out will result in excessive wear on the inside edges.
The caster angle refers to the amount of forward or rearward tilt of the steering axis. Positive caster means the steering axis is sloped to the rear while the more uncommon negative caster slopes to the front. Different caster angles can affect the how heavy the steering feels but also straight line stability so it’s important these are set correctly.
The thrust angle refers to the direction that the rear wheels point in relation to the centre line of the vehicle. If the thrust angle is not zero, i.e. the rear wheels are not at right angles to the centre of the vehicle, it will ‘crab’ or move sideways from the rear of the car.