Wheel Weight
A small metal weight attached to a wheel rim to correct imbalances and ensure smooth tire rotation.
A wheel weight is a small counterweight made of lead, steel, or zinc that is attached to a wheel rim during the wheel balancing process. Because tires and wheels are never perfectly uniform in weight distribution, they will wobble or vibrate at high speeds unless balanced.
A wheel balancing machine spins the wheel assembly, detects the heavy spots, and indicates exactly where and how much weight needs to be added to the opposite side to balance it. Wheel weights are either clipped onto the outer lip of the rim (clip-on weights) or adhered to the inner barrel of the wheel (adhesive weights).
If a wheel weight falls off, the tire will become unbalanced, causing a noticeable vibration in the steering wheel, floorboards, or seat, typically at speeds above 50 mph. Replacing missing weights and rebalancing tires prevents uneven tire wear and suspension fatigue.