ASE G1 Auto Maintenance and Light RepairSuspension and SteeringEasy
A customer complains of a rhythmic 'thump-thump-thump' noise that increases in frequency with vehicle speed and is most noticeable at low speeds. The technician inspects the tires and finds a flat spot on one of the front tires. Which of the following is the MOST likely cause of this condition?
- AWorn shock absorbers
- BA seized brake caliper
- CIncorrect toe-in setting
- DExcessive positive camber
Show answer & explanationAnswer & explanation
Correct answer: B. A seized brake caliper
A seized brake caliper can cause a brake pad to remain in contact with the rotor, leading to localized overheating and wear on the tire in one spot, creating a flat spot. This flat spot will then produce a rhythmic thumping noise as the tire rotates.
Why the other options are wrong
- A. Worn shock absorbers primarily affect ride quality and control, leading to cupping or irregular wear, not typically a single flat spot.
- C. Incorrect toe-in causes feathering or rapid wear across the tire tread, not a specific flat spot.
- D. Excessive positive camber typically causes wear on the outer shoulder of the tire, not a flat spot.
Flat Spot on Tire
A localized area of excessive wear on a tire's tread, often caused by sustained braking or a mechanical issue, leading to a rhythmic thumping noise.
- Causes rhythmic thumping noise.
- Increases with vehicle speed.
- Often due to braking issues or prolonged parking.
Memory trick: Flat tires cause a thump, think 'brake' for the bump.