Reasons for Abnormal Noise When Releasing the Brake on BMW X3 During Start-up?
4 Answers
BMW X3 produces abnormal noise when releasing the brake during start-up, which is a normal phenomenon for automatic transmission vehicles. The brake noise is caused by the gap in the brake pads. Below are the relevant introductions: Model Introduction: The BMW X3 is an SUV model with unique characteristics, introducing the new concept of a Sports Utility Vehicle (SUV) and equipped with BMW's patented xDrive intelligent all-wheel-drive system. Design Style: The BMW X3 combines the distinctive proportions of a Sports Utility Vehicle with classic and innovative design elements, featuring a fresh and youthful exterior while emphasizing the design characteristics of the BMW brand—robust and powerful. Additionally, the interior space of the BMW X3 can accommodate five people along with a large amount of luggage or sports equipment, providing more convenience for travel. Currently, the BMW X3 is the latest model in its series.
I've also experienced that squeaking noise when releasing the brake during initial acceleration in my BMW X3, which is quite common. In most cases, it's caused by rust on the brake discs, especially after the car has been parked for several days in humid conditions, leading to rust formation on the metal surface. When you start moving, the brake pads rubbing against the discs produce that clunking sound. After driving a bit and applying the brakes a few more times, the rust wears off and the noise disappears. If the noise persists continuously, you should be more cautious: it might indicate that the brake pads are nearly worn out and have become too thin for proper contact; or the brake discs might have warped or become uneven, often due to aggressive driving or frequent high-speed braking; alternatively, the caliper might not be retracting properly, getting stuck and causing the noise. These minor issues aren't major problems, but don't delay addressing them as they can affect braking performance. I recommend checking the brake pad thickness weekly—if there's less than 3mm left, it's time to replace them. Or, when washing the car, rinse the brake area to remove rust, which is both cost-effective and convenient. The noise occurs more frequently during rainy days or cold winter starts, but there's no need to worry about it.
As a car enthusiast, when my BMW X3 makes abnormal noises upon releasing the brake to start, I often suspect it's related to the braking system. That 'squeaking' sound during startup could stem from the brake pad material: pads with high metal content tend to create noise when rubbing against the disc during cold starts. It might also be due to rust layers on the brake discs, which commonly occur after prolonged parking. Additionally, loose drivetrain components like half-shafts or suspension ball joints can produce noises when subjected to force during startup. If the vehicle has been modified, improperly installed aftermarket parts could also trigger abnormal sounds. From my observation, the noise becomes more noticeable after high-speed driving followed by cooling and then restarting; trying to warm up the car and gently applying the brakes before starting can reduce the sound. In the long run, switching to high-quality ceramic brake pads can minimize friction noise, or having the calipers and brake component clearances checked at a garage every six months ensures everything is in order. From a safety perspective, frequent abnormal noises warrant immediate diagnosis to prevent them from escalating into brake failures.
Having worked on many BMW X3 models with this issue, the 'clicking' sound when releasing the brake at startup is mostly caused by the brake system. Rusty brake discs are the most common culprit, as they can develop rust after just a few days of parking; worn-out or uneven brake pads can also create friction noise. Stuck caliper pistons or loose return springs may lead to persistent sounds. Additionally, if the drive shafts or suspension bushings are aged and cracked, they can produce creaking noises when pressure is applied during startup. When inspecting such vehicles, I first check the brake discs for scratches or rust, then measure if the pad thickness meets standards. Improper daily operations, like slamming the brakes after driving through water, can easily cause rust buildup. Therefore, I advise owners to avoid parking in damp areas and to warm up the car for a minute during cold starts. If the noise is mild, repeatedly applying the brakes can help wear off the rust. If the noise persists for over a week, it's best to visit a professional shop for a brake system safety scan.
