ASE G1 Auto Maintenance and Light RepairSuspension and SteeringEasy
Which of the following wheel alignment angles primarily influences tire wear on the inner or outer edge of the tread?
- AToe.
- BSetback.
- CIncluded angle.
- DCaster.
Show answer & explanationAnswer & explanation
Correct answer: A. Toe.
Toe is the most critical alignment angle affecting tire wear on the inner or outer edges. Incorrect toe causes the tires to scrub sideways as they roll, leading to rapid and uneven wear.
Why the other options are wrong
- B. Setback refers to the position of one front wheel relative to the other, indicating a bent frame or suspension component.
- C. Included angle is the sum of camber and steering axis inclination, used for diagnostic purposes but not a direct cause of edge wear.
- D. Caster affects steering stability and effort, not direct tread wear patterns.
Toe Alignment and Tire Wear
Incorrect toe setting causes tires to scrub sideways as they roll, leading to rapid and uneven wear on the inner or outer edges of the tread.
- Toe-in means the front of the wheels are closer together than the rear.
- Toe-out means the front of the wheels are further apart than the rear.
- Excessive toe-in causes outer edge wear; excessive toe-out causes inner edge wear.
Memory trick: Toe's scrub wears the tire's edge.