Reasons for Abnormal Noises When Braking and Releasing in BMW 3 Series
2 Answers
The following are the reasons related to BMW 3 Series: 1. Squealing noise: If it's a squeal, check if the brake pads are nearly worn out (the warning tab is making noise). If they are new pads, check for any foreign objects caught between the brake disc and pads. 2. Dull noise: If it's a dull sound, it's mostly an issue with the brake caliper, such as worn sliding pins or detached spring plates. 3. Hissing noise: If it's a hissing sound, there could be multiple issues—problems with the caliper, brake disc, or brake pads. If the noise is continuous, first check for any dragging brakes, as poor caliper retraction can cause prolonged friction between the disc and pads, leading to abnormal noises under certain conditions. Also, check for any foreign objects stuck between the pads and disc. If the pads are new, inspect whether the brake disc has grooves, as localized friction can cause noise. If the disc is fine, consider whether the brake pads are too hard or if the noise insulation shims were installed incorrectly. If the noise occurs only during braking, it's likely due to excessively hard brake pads.
As a seasoned driver with over a decade of experience, my BMW 3 Series also encountered the issue of clunking noises when braking to a stop and releasing. Looking back, the reasons were actually quite common. Brake pads worn to their limit or contaminated with dust and gravel can cause friction noises; uneven brake discs or rust are more noticeable in damp and cold weather; noises upon release are often due to sticky calipers, insufficient lubrication, or small stones getting stuck. Newly replaced brake pads sometimes require a few hundred kilometers of breaking in to become silent. Ignoring these minor sounds may lead to longer braking distances or system damage—I learned this the hard way by neglecting them and ended up spending a lot on brake disc repairs. Especially when driving on highways or downhill roads, the safety risks are significant. I always recommend getting a trusted mechanic to check the brake pad thickness, disc condition, and the overall system. While BMW's quality is excellent, timely maintenance ensures both safety and cost savings.
