What Causes the Hissing Sound When Suspension Goes Over Bumps?
2 Answers
Suspension making a hissing sound when going over bumps is due to shock absorber oil leakage or shock absorber bending. Here are the specific manifestations of shock absorber failure: 1. Abnormal noise: If the vehicle makes abnormal noises when driving on bumpy roads, it is highly likely that the shock absorber is damaged. 2. Oil leakage: When inspecting the shock absorber through the wheel arch with a flashlight, if oil leakage is observed on the exterior of the shock absorber, it indicates the shock absorber is already damaged. 3. Loose chassis: When driving on bumpy roads, if the vehicle body exhibits excessive bouncing or unstable swaying, it usually indicates a problem with the shock absorbers.
Last time I drove my old car over a speed bump, I also heard a 'hissing' sound of air leakage, which is mostly due to the aging of the shock absorber oil seal. There is gas or oil pressure inside the shock absorber, and when hitting bumps with strong impact, the rubber seal can crack and leak, causing noise. If left unattended for a long time, the air leakage will become more obvious, the damping effect will deteriorate, the body will become bumpy and unstable, and it may even skid when braking. It is recommended to check the chassis rubber parts every quarter to prevent dust clogging and accelerate wear. For maintenance, choose good roads to drive on, avoid too many potholes, and reduce part fatigue. I have replaced the oil seal myself, it's not difficult but requires professional tools, so beginners are better off going to a repair shop. Overall, early treatment can save money on major repairs and improve driving comfort.
