Will Rusty Brake Discs Cause Abnormal Noises?
3 Answers
Abnormal noises may occur. When brake discs are severely rusted, normal braking cannot achieve the ideal effect of grinding off the rust. Severe rust on the brake discs can cause an uneven surface, leading to issues such as steering wheel vibration and abnormal noises when braking. Below are the reasons why rusty brake discs may produce abnormal noises: 1. Slight rust on the brake disc surface: This can be removed by continuous braking while driving, and no special treatment is needed because a small amount of rust on the brake discs will be worn off by braking during vehicle operation. If the rust is more severe, it may cause vibrations or shaking during braking, such as brake pad vibration, steering wheel vibration or shaking, or body vibration. Of course, this is under the premise of ensuring safety and not affecting public traffic. While driving, gently apply the brakes to let the friction between the brake pads and the brake discs 'polish' the surface. 2. Severe rust on the brake discs: When there is a significant amount of rust, it can cause an uneven surface on the brake discs, leading to noticeable body vibrations during braking. The driver can clearly feel abnormal sensations in the brake pedal, steering wheel, and body. In such cases, it becomes difficult to remove the rust, and even if 'polishing' is attempted, it may result in abnormal wear of the brake pads and continued vibrations. Therefore, it is recommended to perform maintenance on the brake discs every two months to prevent excessive rust development.
Rust on brake discs can indeed cause abnormal noises, especially on rainy days or in humid conditions. I've seen many older cars parked outdoors for long periods develop brown rust spots on the disc surface. When braking in this condition, it sounds like sandpaper grinding against metal – a particularly harsh squealing noise. The principle is simple: rust creates uneven surfaces on the otherwise smooth metal, causing friction noises when brake pads press against them. However, this situation is usually temporary. Driving out and applying a few hard brakes to wear off the rust typically eliminates the noise. But if recurring rust is accompanied by persistent abnormal sounds, the brake disc may be warped or deeply corroded. In such cases, it's advisable to visit a professional shop for disc surface flatness testing. For daily parking, try to choose dry locations, and remember to apply several brakes after rain to evaporate moisture.
Brake disc rust causing noise is quite common, especially during spring humidity or in coastal cities. When cast iron brake discs encounter moisture, they quickly develop an oxide layer on the surface - like putting sandpaper on the disc. When you drive in the morning, a light brake application produces sharp grinding sounds that can startle new drivers. Actually, there's no need to panic. Typically, driving 1-2 kilometers with repeated braking will wear off the rust layer and restore quiet operation. However, I must warn that if the car sits unused for 3-4 days during rainy season, the rust layer may become thick enough to damage brake pads. In such cases, it's best to first drive on open roads to wear down the rust, never go directly on highways. When washing your car on weekends, immediately drive to evaporate water from the brakes after rinsing them. For long-term outdoor parking, applying anti-rust spray to brake discs is recommended.
