Properly balanced tires are important for driving comfort and long tire life. Unbalanced tires can cause vibration, resulting in driver fatigue, premature tire wear and unnecessary wear to your vehicle's suspension. Tires should be balanced when they are mounted on wheels for the first time or when they are remounted after repair. Tires should be rebalanced at the first sign of vibration or "shimmy." Vibration may also be due to misalignment or mechanical problems.