ASE A4 Suspension and SteeringSuspension System Diagnosis and RepairMedium
A vehicle with a multi-link rear suspension exhibits a 'clunking' noise from the rear when accelerating or braking. The technician suspects a worn component. Which of the following is MOST likely the cause?
- ALoose wheel bearing
- BWorn shock absorber mount
- CWorn trailing arm bushing
- DCollapsed jounce bumper
Show answer & explanationAnswer & explanation
Correct answer: C. Worn trailing arm bushing
Clunking during acceleration and braking in a multi-link rear suspension often indicates excessive play in components that control fore-aft wheel movement. The trailing arm, with its large bushing, is primarily responsible for this, and wear in its bushing allows the wheel assembly to move forward and backward excessively, causing a clunk.
Why the other options are wrong
- A. A loose wheel bearing usually causes a humming or grinding noise and wheel play, not a distinct clunk during acceleration/braking.
- B. Worn shock absorber mounts can cause clunking, but typically over bumps or during suspension compression/rebound, not specifically during acceleration/braking.
- D. A collapsed jounce bumper causes a harsh bottoming-out sensation, not a clunk during acceleration/braking.
Trailing Arm Bushing Wear
Wear in the rubber or polyurethane bushing of a trailing arm, which connects the wheel hub to the chassis and controls fore-aft wheel movement.
- Causes clunking during acceleration and braking.
- Can lead to unstable handling.
- Requires visual inspection for cracks or tears.
Memory trick: When the links get loose, the 'TRAIL' of sound follows the accel/brake.