Why does a new car's brakes make noise?

[MadelineRose]

The reasons why a new car's brakes make noise are: 1. The brake pads rusted during storage; 2. Newly replaced brake pads haven't been broken in; 3. The brake pads weren't installed properly during assembly; 4. Use of inferior or overly hard brake pads; 5. There is sand or foreign objects between the brake pads and brake discs. Precautions for braking in a new car are: 1. Release the brake once before the vehicle comes to a complete stop, then gently apply the brake until the vehicle stops moving; 2. Reduce speed sufficiently by braking before entering a curve; 3. Pay attention to controlling speed when driving in rainy weather, use emergency brakes cautiously to avoid skidding and rollover.

[DelMiles]

When I first bought my new car, there was always a slight squeaking sound when braking, which puzzled me. After asking friends, I learned that this is mostly because both the brake pads and brake discs are brand new, with surfaces not yet perfectly smooth, plus some residual protective grease from the factory, causing noise during braking. Especially after sitting overnight or in rainy weather when the air is humid, the brake discs can rust, leading to a squeaking sound when first driving, which disappears after a few stops. It's recommended to drive more medium to long distances before the first service to allow the braking system to heat up and wear in properly, avoiding frequent short trips or sudden stops. Parking in dry places can reduce the chance of rust, and after a break-in period of about 500 kilometers, the noise usually disappears. If the sound is harsh and accompanied by vibration, it's best to check for installation issues at a repair shop. In short, noises from a new car are often minor and not worth too much worry.

[FaithLynn]

As someone who frequently pays attention to automotive details, I've seen many cases of new car brake noise. The main reason is insufficient component break-in: brake pads often contain metallic materials, and their rough surfaces when new cause friction noise; the initial smoothness of the brake rotors isn't perfect, and residual factory anti-rust oil can also contribute. Moisture is a significant factor—parking in damp, cold conditions can lead to rust on the rotors, making the noise more noticeable. I recommend driving more on medium-speed roads during the break-in period to raise the system temperature and remove rust, while avoiding parking in the rain to prevent moisture buildup. After 200-800 kilometers of break-in, the noise usually subsides, but don't neglect safety checks during this process. High-performance brake pads may produce slightly more noise by design, which is normal. If unusual noises persist or the brakes feel spongy, consult a professional immediately—don't compromise travel safety.

[VanLily]

I often hear noises when braking, especially during the initial period with a new car. This is usually nothing serious. Minor gaps or uneven surfaces on newly installed brake pads can cause normal friction sounds. Moisture-induced rust often leads to noises when applying the brakes initially. Safety first - if it's just slight squeaking at low speeds that disappears after driving a few dozen kilometers, it can be ignored. But if there's sharp screeching or a sticking sensation, stop and inspect immediately. I make a habit of driving new cars frequently to prevent rust from component inactivity, and always park in dry locations to eliminate moisture sources. Most noises are just break-in sounds that naturally quiet down with increased mileage.