ASE A4 Suspension and SteeringWheels and Tires Diagnosis and RepairMedium
A technician is diagnosing a vehicle with a persistent grinding noise that gets louder when turning right and quieter when turning left. The noise is constant, regardless of braking. Which component is MOST likely faulty?
- ALeft rear wheel bearing
- BLeft front wheel bearing
- CRight rear wheel bearing
- DRight front wheel bearing
Show answer & explanationAnswer & explanation
Correct answer: B. Left front wheel bearing
When a vehicle turns right, the weight shifts to the left side, increasing the load on the left wheel bearings. If a bearing is faulty, this increased load will make the grinding noise louder. Conversely, turning left shifts weight away from the left bearing, making the noise quieter.
Why the other options are wrong
- A. Rear wheel bearings typically cause noise that is less affected by steering input.
- C. Rear wheel bearings typically cause noise that is less affected by steering input.
- D. Turning right would unload a right wheel bearing, making its noise quieter if faulty.
Wheel Bearing Load Diagnosis
A faulty wheel bearing's noise typically gets louder when turning in the direction that loads that bearing, and quieter when turning in the opposite direction.
- Turning right loads left side bearings
- Turning left loads right side bearings
- Noise increases with load on faulty bearing
Memory trick: Turn right, load left; turn left, load right.