Uneven tire wear can compromise safety and create a need for early tire replacement. Several things can cause this type of wear, including lack of regular vehicle maintenance, alignment issues and worn vehicle components that affect the tires. The first signs of uneven tire wear signal a problem that must be resolved quickly so the tires do not become significantly damaged.
When tread is deeper on the edges than in the middle, the tire is overinflated. In contrast, when the tread is deeper in the middle than the edges, the tire is underinflated.
If a tire has raised bumps on it, commonly called scallops, the tires are probably not being rotated often enough.
Worn shocks or struts also can cause uneven tire wear.
Driving a vehicle that is out of alignment can cause uneven tire wear. A common symptom is a vehicle that drifts away from straight tracking on a straight and level road.
Alignment components can become worn and cause problems. In sharp turns, for instance, tire angles may not compensate properly, and the tires may squeal.
Improper wheel balancing also can cause uneven tire wear because of excess vibration. This can show up as a scalloped or cupped wear area on the tires.