I have a 2016 535i and was told by dealer breaks need service in 1000 miles. can rotors be cut and if not are the drilled slotted
Yes, rotors can be machined ("turned") in the event they are measured and found to be out of tolerance or uneven on the surface, which can cause a bit of vibration when using your brakes. It sounds like you may have drilled and slotted rotors, but in either case they can be machined. With drilled and slotted rotors, extra care must be taken to ensure the cutting or machining is done properly in order to avoid damaging the slotted and drilled sections of the rotors.
When you press on your brake pedal, this activates a hydraulic pressure which forces small pistons inside your brake calipers to push the brake pads against the brake rotors which is what causes the stopping power you are familiar with when pressing your brake pedal. When this happens, an enormous amount of heat is generated due to the friction between the brake pads and rotors. The brake rotors eventually cool down and then heat up again the next time you press on the brakes. Over time this can cause them to warp slightly causing very small low spots on the surface of the brake rotor. When this happens and the brake pads are applied again to the rotors, this causes an uneven surface (on the rotor) to be applied to the flat surface brake pad, which can cause a vibration, shaking or very loud grinding sound. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your brake rotors.
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