Why Does the Shock Absorber Make Metal Noise When Cold but Not When Hot?

[SanAnthony]

This situation usually occurs due to oil leakage from the shock absorber or damage to the shock absorber itself. The owner can inspect it themselves or visit a professional 4S shop or repair shop for inspection and maintenance, which may involve replacing the shock absorber. Below is some relevant information: 1. Definition of Shock Absorber: The car shock absorber (including the shock spring) is the most important component in the vehicle's vibration filtering system. 2. Function of Shock Absorber: It absorbs vibrations and impacts caused by uneven road surfaces during driving, thereby providing a comfortable ride for passengers. 3. Hazards of Damaged Shock Absorber: Once the shock absorber is damaged, the vehicle may experience excessive bumpiness and instability while driving, which can severely impact driving safety in serious cases. 4. Common Damages to Shock Absorbers: (1) Abnormal Noise: If the shock absorber makes unusual noises when driving on bumpy roads, it is highly likely that the shock absorber is damaged. (2) Oil Leakage: By using a flashlight to inspect the shock absorber through the wheel arch, if oil leakage is observed on the exterior of the shock absorber, it indicates that the shock absorber is already damaged. (3) Loose Chassis: When driving on bumpy roads, if the vehicle's body exhibits excessive bumpiness and instability, it is often a sign that the shock absorber is malfunctioning.

[Steven]

As a veteran driver with over a decade of experience, I often encounter the issue of metal noises from shock absorbers during cold starts that disappear after the car warms up. This problem is particularly noticeable on winter mornings when lower temperatures cause rubber components like bushings to contract and harden, increasing gaps and causing friction against metal parts, resulting in clicking sounds. After the car warms up and temperatures rise, the rubber softens and the noise vanishes. If ignored over time, increased friction can wear down the suspension system, affecting driving stability and comfort. For example, last winter, my car made noises every time it went over speed bumps. A later inspection at the repair shop revealed that the top buffer was aged, and applying some lubricating grease solved the problem. I recommend addressing similar noises promptly by having a professional technician diagnose the issue early. During regular maintenance, also pay attention to lubricating shock absorber components to prevent minor issues from escalating. Safety should always come first.

[DiMia]

Having been involved in car modifications for years, I've studied suspension systems extensively. The phenomenon of metal knocking sounds from shock absorbers when cold but silent when warm is quite typical. At low temperatures, rubber bushings lose elasticity and shrink, creating gaps with the metal frame that cause friction noises. After the car warms up, the rubber regains elasticity and lubrication, eliminating the sound. I've personally handled similar issues by applying high-temperature resistant lubricant to connection points, which proved very effective. However, if the noise worsens, it may indicate severely aged bushings requiring replacement parts like spring seats or buffer washers. When modifying shock absorbers, always choose high-quality components to avoid frequent malfunctions. Note that unresolved knocking sounds can affect vehicle handling, potentially causing skidding on bumpy roads and posing safety risks. Regular inspection and maintenance can extend shock absorber lifespan and ensure safer driving.

[LaAnnie]

Driving safety is my top concern. The main reason for metal noise from the shock absorber during cold starts, which stops after the car warms up, is that low temperatures cause rubber components to harden and rub against metal. The noise disappears when they soften with heat. However, if this issue is not addressed, it can increase suspension wear and potentially lead to imbalance during high-speed driving or turns, raising the risk of accidents. I recommend promptly visiting a repair shop for inspection and diagnosis. Simple lubrication or replacement of small components like aged bushings may be needed to prevent the problem from worsening. Maintaining good vehicle condition is crucial for daily driving—don't let a minor noise issue turn into a safety hazard.