Turning brake rotors?

hbmike said:

I had BMW replace my rear pads, but they didn't replace the rotors, as they said it was still .5 above the minimum. They also did not turn the rotors as well. My service tech said that BMW does not turn their rotors.

My question, isn't this bad? Shouldn't you turn the rotors with new brake pads? Plus the old stock pads were pretty abrasive, and left the rotors with a nice lip, so the rotor is definitely not smooth.

Need some advice, as I plan on changing the rear pads to a dustless pad.

Thanks

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BMW does NOT recommend turning the rotors since BMW OEM rotors are softer and that turning or lathing the rotors will make it dangerously close to the minimum thickness required. When they turn/lathe the rotors they'll need to take off another layer of the surface of the rotor and that will make the rotors prone to warping or cracking.

If you change the rear to a dustless pad be sure you change the rotors to something that'll withstand the harder pads as well. The OEM rotors are soft and will definately warp if you mate it with dustless pads.

Not necessary.

Turning the rotors isn't necessary unless they are warped. Even if they have minor grooves in them, it really isn't necessary. You'll be fine, just keep in mind that you will most likely need to replace the rotors next time you do pads (or possibly sooner).