What is the reason for a lot of brake dust on the front wheel hubs of a BMW?
2 Answers
Brake pads are used for friction braking and will inevitably produce wear material, so the appearance of brake dust on the front wheels is a normal phenomenon. Brake wear: Severe wear of the brake pads causes the caliper to reach its maximum limit and become stuck without retracting. This is common in older vehicles that have been used for a long time. Replace the brake pads. High resistance in the brake cable: Excessive resistance in the brake cable is often due to rust or ice inside the cable, or oil contamination and dust buildup causing stickiness. It is recommended to replace the brake cable. Rear brake caliper wear: Severe wear of the rear brake caliper. This is common in older vehicles that have had their brake pads replaced, where the working surface of the caliper is severely worn and becomes stuck.
I've been driving a BMW for over ten years, and the front wheel rims always get covered in brake dust. This is mainly determined by the material of the brake pads. Some BMWs use semi-metallic brake pads that shed more dust during friction, even more than ceramic pads. Additionally, frequent stop-and-go driving in urban traffic makes it easier for dust to accumulate. Over time, the dust can corrode the wheel rim's paint or affect its appearance. My experience is to check the thickness of the brake pads and replace them with new low-dust pads if they're too thin. When washing the car, use a brush to clean the inside and outside of the rims, and sweep them weekly to prevent buildup. The dust sticks more in humid weather, so you need to be more diligent. Overall, this doesn't affect braking performance, but don't neglect maintenance. Driving smoothly and reducing sudden braking can effectively reduce the amount of dust.
