Reasons for Abnormal Noises When Passing Over Speed Bumps
3 Answers
When passing over speed bumps, the repeated abnormal noises are often due to the friction sound from the stabilizer bar bushings. These bushings tightly wrap around the metal rod, and when going over speed bumps, the rotation of the metal rod against the bushings produces the noise. Generally, this sound cannot be heard from outside the vehicle. Additionally, if the installed engine guard is deformed or the screws are loose, it can also cause abnormal noises while driving. Furthermore, unauthorized modifications to wiring or the installation of electrical devices in the engine compartment that are not securely fixed can lead to such noises. Below is some relevant knowledge about shock absorber inspection: Check the shock absorbers for any deformation or oil leakage. The shock absorber top mount has three screws, which should be tightened with a wrench. The issue might also be caused by dry friction due to insufficient lubrication of the upper and lower shock absorber bushings. These can be removed and lubricated with grease.
I drive for quite long hours and often hear creaking sounds when going over speed bumps. I figure it's probably due to aging or oil leakage in the shock absorbers. It could also be that the connections of the stabilizer bar have loosened, with long-term vibrations causing component wear and accumulated abnormal noises. The undercarriage of the vehicle tends to accumulate dirt, which exacerbates friction sounds. When discovering such issues, it's best to regularly inspect the suspension system to prevent minor problems from turning into major ones, affecting driving stability. Once, my car had this issue delayed for too long, and the suspension bolts almost came loose, nearly causing an accident. So now, whenever I hear strange noises, I take them seriously immediately.
As an average car owner, unusual noises when going over speed bumps may originate from problematic shock absorbers or bearing wear. Loose or damaged chassis components such as control arms or springs can also produce rattling sounds. This is often accompanied by increased body sway, so it's advisable to first visually inspect around the tires for obvious looseness before heading to a professional shop for comprehensive diagnostics. Ignoring these issues can degrade vehicle handling and increase risks during cornering. Personally, I've tried tightening bolts myself, but most situations still require professional tool-based repairs.
