ASE G1 Auto Maintenance and Light RepairSuspension and SteeringMedium
A customer complains of a persistent 'squeaking' noise coming from the front suspension, especially when driving over bumps or uneven surfaces. The noise is more prominent in colder weather. Upon inspection, the technician finds no visible leaks or loose components, but notices some dry-rotted rubber bushings on the sway bar end links. Which of the following is the most likely cause of the squeaking noise?
- AFailing strut mounts
- BLoose wheel bearings
- CWorn ball joints
- DDry or deteriorated sway bar bushings
Show answer & explanationAnswer & explanation
Correct answer: D. Dry or deteriorated sway bar bushings
Dry or deteriorated rubber sway bar bushings are a very common cause of squeaking noises in the suspension, particularly over bumps and in colder weather when the rubber becomes stiffer and less pliable. The metal sway bar rubbing against the dry rubber creates the squeak.
Why the other options are wrong
- A. Failing strut mounts can cause clunking or thumping, and sometimes a groaning noise, but a distinct squeak is less common.
- B. Loose wheel bearings typically produce a growling or humming noise that changes with speed, not a squeak over bumps.
- C. Worn ball joints typically cause clunking or popping noises, not usually a persistent squeak.
Sway Bar Bushing Squeak
Dry or deteriorated rubber bushings on the sway bar or end links can cause a persistent squeaking noise, especially when the suspension moves over uneven surfaces.
- Common in colder weather.
- Noise occurs over bumps.
- Caused by metal-on-dry-rubber friction.
Memory trick: Squeaky Sway Bar, a Dry Rubber's Plea, for a Drip of Lube, or a Bushing New Be.