Tire balance, also called tire unbalance or tire imbalance, describes the distribution of mass within an automobile tire or the entire wheel on which it is mounted.Tire balancing is a tune-up for your wheel-tire set. When all areas of the wheel-tire unit are as equal in weight as possible, the tire will roll smoothly. This helps it wear evenly, for longest life. Balancing also contributes to ride comfort: Imbalanced tires will wobble or hop up and down, which causes vibration.
If a wheel is out of balance, it will cause a vibration that can felt in the steering wheel and/or seat, while a wheel out of alignment can cause excessive tire wear as well as steering problems. Wheel alignment consists of adjusting the wheel angles so they are perpendicular to the ground and parallel to each other. If your entire vehicle is shaking, that's another sign of an unbalanced tire. If your steering wheel is shaking, your front tires may be unbalanced. Unbalanced rear tires can cause your seat to shake.