Why does the car make abnormal noise when starting and braking?

[VanMary]

There are several reasons for abnormal noise when starting and braking: 1. For automatic transmission cars, the noise is caused by releasing the brake too slowly, resulting in a squeaking sound when starting. 2. The brake disc and brake pads are stuck together due to rust, causing abnormal noise. This usually happens after driving in rainy weather or after the car has been parked for a long time. The brake disc and brake pads rust and stick together, and when the car is started again, abnormal noise occurs. This can be solved by applying butter or special lubricating oil to the connection between the brake pads and the brake caliper. 3. Due to low temperatures, the rubber parts of the suspension become harder, and the surfaces of the brake disc and brake pads also change, resulting in abnormal noise when starting. This will improve after the car warms up. 4. Both the brake disc and brake pads are high-wear items. Every time the brakes are applied, these two parts rub against each other, leading to natural wear over time. When the wear becomes excessive, abnormal noise will occur, so regular inspection and replacement are necessary.

[IsabellaFitz]

I've been driving for almost 30 years and have encountered quite a few instances of squeaking sounds during starting and braking. The common causes are mainly rust on the brake discs, especially when parked outside on rainy days or in the morning with high humidity—friction upon starting causes that squeaking sound. Another reason is when the brake pads are nearly worn out, and the metal layer directly rubs against the disc, creating loud and dangerous noises. I once delayed addressing it and ended up spending a lot on repairs. Additionally, dust buildup inside the wheel hub or insufficient lubrication of the brake calipers can also cause abnormal noises. For safety, I recommend not ignoring such issues—get your brake system checked at a professional repair shop as soon as possible. Regular maintenance, like rinsing the wheel area during car washes to reduce dirt buildup, ensures a safer and more worry-free drive.

[LaNoah]

On my daily commute, whenever the screeching sound from braking gets loud, it really bothers me. During the morning rush hour with heavy traffic, that squeaky noise is distracting. A friend mentioned it's likely due to thin brake pads or rust buildup after sitting for a few days. After experiencing this myself, I've made it a habit to lightly press the brakes a few times before parking to cool them down, and the noise is indeed reduced the next day. Alternatively, using a high-pressure water hose to rinse the wheels helps remove dirt easily. Of course, driving habits also play a key role—avoiding sudden braking and rapid acceleration reduces wear and tear, which naturally minimizes odd noises. Regularly having a mechanic check the brake pad thickness, say once a month, prevents minor issues from turning into major risks, making life easier, safer, and more worry-free.

[McCora]

When checking your car by yourself, starting brake noise is often caused by rust or dirt. The general steps are to clean the rust layer on the disc surface with a soft cloth; check how much brake pad thickness remains, and replace them if severely worn; lubricate the caliper slides for smooth operation. Never force it—if unsure, it's safer to have it handled by a professional shop. Remember, paying attention to these details during car maintenance can prevent problems, ensuring a quieter, more comfortable, and worry-free drive.

[VonEsther]

Don't underestimate abnormal noises when starting or braking during safe driving. It could be an alarm for brake system issues, such as rust, wear, or dust causing jamming. When the noise becomes loud, reaction time in emergencies slows down, increasing accident risks. After noticing this, I always prioritize addressing it: pay attention to the sound frequency every time I start the car, and if it persists for several days, take it to the 4S shop for inspection immediately; park in sheltered areas to avoid rain and keep the car clean by washing it regularly. Addressing minor issues early not only protects the components but also ensures safe driving without risks.

[VincentMarie]

Passionate about automotive mechanics, the squeaking noise during initial braking is often caused by thermal expansion/contraction or rust, especially when cold starts cause component shrinkage and friction sounds. Alternatively, the brake pad material may have degraded – after upgrading to premium materials, I experienced significantly less noise. Solutions include resurfacing rotors for smoothness, checking brake fluid levels, and ensuring caliper operation is normal. For persistent issues, upgrading to OEM parts early is advisable. Driving habits matter too: avoid slamming brakes when the car is cold, and gentle starts reduce wear. This ensures stable performance and worry-free driving.