When you visit your Goodyear tire shop for tire related matters, the technician will use terms that might seem strange to you. This tire technician will say that it is best you do what he advises or you could lose control of your car or worse have an accident when on the road and so you, without knowing what he is doing….(for some of you)……..will agree and pay the bill after. Let us explain what is being done.
Next time when the technician checks your car for wheel alignment issues you will understand that there are primarily three things they look at – Camber, Caster and Toe. Let us look at each in detail.
Camber
It is the angle of the wheel when viewed from the front of the car. The camber is positive if the wheel is tilted out and negative if the wheel is tilted in. A camber that is out of adjustment will cause tyre wear on one side of the tyre. This is what causes your car to pull to one side (with positive camber) of the road and you’ll find yourself applying pressure incessantly to keep the car moving straight. If you notice these symptoms then it’s time to have the wheel alignment checked. After your wheel alignment issue is fixed, you may still experience the pulling problem because of an uneven tyre. The best thing to do in this case is to replace the tyres.
Caster
It’s the angle/tilt of the steering axis when viewed from the side of the car. It is positive if the tilt is towards the driver and negative if the tilt is forward. When the caster is out of adjustment it doesn’t cause tyre wear but affects steering stability and steering effort. A lot of vehicles have a little bit of positive caster which allows for quick steering return and stability at high speed.
Ideally, your car must drive straight (on a straight road) with very little steering effort, like a bicycle. Plus the steering wheel must spin back to straight position after completing a turn.
When the caster is out of specifications, it causes problems in straight line steering and the vehicle starts to wander. There are many reasons for caster misalignment such as bent spindle, weak spring, worn out control arm bushing, bent strut and also ride height.
Toe
Imagine that your feet are tyres. Try walking with toes pointed out and then with toes pointed in. Now apply this to the front tyres of your vehicle. The wheels must ideally be parallel. The distance between the leading edge and the trailing edge of your front tyres must be the same. If it is then the wheels have a “zero toe”. If the front the edges are closer than the rear edges, then it’s a toe-in and if they are far apart then it’s a “toe-out”. These can cause severe uneven wear to tyres.
Toe problems are the most critical wheel alignment issues and they cause severe tyre problems. Replacing tyres doesn’t resolve the problem unless the cause for misalignment is identified and fixed and toe is set to manufacturer specifications.
So, now you know and you can share this information with your family and friends.
