Why Do Newly Replaced Brake Pads Make Noise?
4 Answers
The reason why newly replaced brake pads make noise is due to mismatched contact surfaces. When installing new brake pads, if the old brake discs are not resurfaced, it can lead to improper installation. Improper installation or failure to resurface the old discs before installing new pads will cause the new pads to rub directly against the uneven surface of the old discs, ultimately resulting in uneven wear of the new brake pads. Brake pads, also known as brake linings, are critical safety components in a car's braking system. The effectiveness of all braking depends largely on the brake pads. Brake pads are generally composed of a steel plate, an adhesive heat insulation layer, and a friction block. The heat insulation layer is made of non-heat-conductive materials to provide thermal insulation. The friction block consists of friction materials and adhesives, which, when pressed against the brake disc or drum during braking, create friction to achieve the purpose of slowing down or stopping the vehicle.
I often heard squeaking noises when I first changed my brake pads, which is mostly because the new pads haven't been properly bedded in yet. The rough surface of new brake pads can cause a squealing sound when rubbing against the brake rotor, just like the creaking sound when walking in new shoes. It takes a few hundred kilometers of driving for them to naturally wear smooth. It's possible that the screws weren't tightened properly during installation, causing looseness or wobbling, or the technician might have contaminated the brake pad surface with grease from their hands. When I encountered this situation before, I would gently apply the brakes a few times to help the surfaces conform. Also, check if the brake caliper isn't retracting smoothly, causing the pads to stay pressed against the rotor, which can affect braking performance. After changing them, it's best not to rush onto highways immediately—try braking several times at low speeds to distribute heat evenly and reduce noise. If the noise persists for more than a week, you should return to the repair shop for inspection, as it might be due to material mismatch or parts issues. Remember, safety first—never ignore abnormal brake noises.
I just bought the car not long ago, and it started making squeaking noises after the first brake pad replacement, which made me quite nervous at the time. After checking, I found out the reasons: the new brake pads were either too hard or not polished smooth, causing friction sounds when rubbing against the old brake rotors. The mechanic mentioned that a break-in period is needed after replacement, so I tried to accelerate this process by applying lighter brakes more frequently while driving. It could also be due to misalignment during installation or dust and debris stuck inside, so it's important to keep the brake system clean. I've just learned to check simple things, like looking for grease residue or loose screws. Although brake noise is common, it can affect braking distance, so I pay attention to the sounds every week and schedule regular maintenance to avoid major issues. By the way, using better-quality brake pad brands can reduce such troubles, so don't skimp on cheap products. This experience has made me pay more attention to the details of my car's condition.
New brake pad squealing is typically caused by rough surfaces rubbing against the rotor, while improper installation such as caliper or shim issues can also lead to noise. After replacement, drive gently for a few hundred kilometers to allow proper bedding-in, which helps the pads and rotor conform smoothly. Contaminants like grease or dust may adhere to the surface—simply clean them during replacement. If the noise persists, inspect the entire braking system, including whether the caliper moves freely. This is akin to new parts needing an initial break-in period. Ensure component quality matches and avoid mixing brands. The noise should fade after bedding-in, and maintenance is key.
