What Causes Noise from Newly Replaced Brake Pads?
2 Answers
The reasons for noise from newly replaced brake pads include foreign object collision, scratches on the brake pads, misaligned installation of brake pads, or inconsistent brake pad sizes. Foreign object collision: While driving, small stones or sand particles on the road may enter between the brake pads and the brake disc, increasing friction and causing noise, which often sounds like a hissing. Don't worry if you hear this sound, as it generally doesn't require repair. These foreign objects will usually fall off as the vehicle continues to move and won't affect the braking system. Scratches on the brake pads: The probability of original brake pads scratching the original brake disc is over 50%. In such cases, the brake pads should be replaced, and the brake disc must first be checked for scratches. If scratches are found, it is recommended to smooth them out or replace the disc. Misaligned installation or inconsistent brake pad sizes: If the brake pads are misaligned during installation, it can cause localized friction and result in noise. Additionally, friction blocks of the same model of brake pads may have inconsistent sizes, especially in width. The size deviation between manufacturers can be up to three millimeters. If improperly sized brake pads are installed, poor fitment can also cause noise. In this case, simply reinstall brake pads that match the original model specifications.
It's actually quite common for new brake pads to squeak when first installed, so don't panic too much. At first, I thought the mechanic installed them wrong, but later learned they need a break-in period, just like new shoes rubbing your feet. When the contact surface between the brake pads and rotors isn't perfectly smooth, it can cause a high-pitched squeal. If there's metal debris stuck in the gaps or moisture from rain, the noise can be even worse. Usually, the noise goes away after driving 200-300 kilometers. If it persists, you should get it checked—it might be due to improperly installed shims or grooves worn into the brake rotors. Remember to avoid hard braking and try driving at a steady speed for a few days.
