There are a few crucial indicators a mechanic will look for to determine what needs to be done to bring the auto alignment back into proper form:
Camber refers to the angle of a vehicle’s wheels and is measured in degrees. When the top of a wheel is tilted out, it is referred to as a positive camber. When the top of the wheel is tilted inward, it is called negative camber.
Having a camber that is out of adjustment causes several issues that will harm a vehicle if ignored. Rapid and irregular wear on the tires is among the most noticeable and immediate issues. Instead of wearing taking place evenly across the tread, premature wear will be focused either on the inside or outside of the tire, depending on whether the camber is positive or negative.
Positive and negative camber may also be a sign of other issues with a vehicle, such as worn springs or bad ball joints. Damage from car accidents may also cause issues with camber.
Caster can be a little harder to visualize, but the appropriate setting is essential to proper handling at higher speeds. A caster line describes whether the pivot axis is pointed forward, or toward the rear.
A negative caster is angled toward the front of a vehicle while a positive caster angles toward the rear. Positive caster will help a vehicle maintain stability at higher speeds, while negative will provide easier steering. Too little caster could cause the vehicle to “wander” or make the wheels shake, sort of like pushing a shopping cart too fast.
Every car manufacturer sets casters to a specific angle to achieve optimal handling for the everyday driver. Casters that deviate from the original setting will cause a vehicle to veer off to the left or right.
The terms toe-in or toe-out are used to describe wheels that don’t match the centerline of a vehicle.
If the distance between the front of a tire and the back of the tires is exactly the same, then the wheels are aligned. However, if the front of the tires are closer together than the back, this would cause a toe-in issue. When the front of the tires are farther apart, the term is toe-out.
The specifications as to how the front and rear tires are set is determined by the vehicle manufacturer. Mechanic shops will use specialized equipment to ensure the tires are aligned to those specifications. A toe setting that is as little as 1/32 of an inch off can cause alignment problems, so precision is key.