I have heard that after machining brake rotors, before they are ready for use, you must prep them for installation by sanding the machined surface lightly with sand paper. Is this so?
No! This does not remove the metal filings caught in the machined surface, and may even add abrasive material to the rotors. Failure to properly clean freshly turned brake rotors causes metal contamination.This may contaminate the ABS wheel sensor and make the ABS operate during slow speed stops. This can also cause uneven pad wear, pulling and noise. Always thoroughly wash the metal filings from machined rotors with hot soapy water. Then dry them with paper towels before installing.
