What Causes the Thumping Noise When Coilover Suspension Goes Over Bumpy Roads?
2 Answers
The reasons for abnormal noise in car coilover suspension are: 1. Loose shock absorber mounting: Long-term vibration during driving can cause the fixing nuts to loosen, leading to abnormal noise from the shock absorber. Solution: Tighten the fixing nuts. 2. Insufficient oil in the shock absorber: Lack of oil can also cause abnormal noise. Check for oil leakage in the shock absorber. If there is leakage, it is recommended to directly replace the shock absorber. If there is no leakage, other components of the shock absorber system need to be inspected. 3. Worn rubber bushings: Wear in the rubber bushings at both ends of the shock absorber can create play at the mounting points, causing noise during driving. Replace the rubber bushings. 4. Deformed components: Deformation of the shock absorber piston rod, cylinder tube, or oil reservoir, or sticking of the piston rod can cause abnormal noise and lead to shock absorber failure, even causing safety hazards. Repair is not recommended (as it is very complicated); it is advised to replace the shock absorber.
When a coilover suspension makes a "dong dong" sound on uneven roads, common causes include loose components or improper installation. If the spring isn't properly preloaded, it tends to sway and collide when bumpy, producing a dull thud. If the top mount bearing or bushings are worn, the metal friction noise becomes particularly noticeable. Internal issues with the shock absorber, such as oil seal leakage or valve failure, can also amplify abnormal noises. I've dealt with similar modified cars myself and found that unsecured fasteners are a critical mistake—when hitting bumps, the components rattle back and forth. Sometimes, it's due to unsuitable preload force chosen during modification, leading to system instability. Remember, regularly checking these details can prevent the noise from worsening. Don't underestimate this small issue—it may accelerate component wear. Getting it adjusted at a professional shop early on saves trouble.
