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I've got a 2013 BMW 335i with M-Sport options. It prompted this question but the issue (and probably the solutions) are not unique to it.

Like many such vehicles, the rear brakes are part drum, part disc. Specifically, the rotor is shaped like a top hat, and the main disc is the brim of the hat, while the parking brake shoes operate on the inside of the main part of the hat. The problem is that the inside of that "hat" and the hub on which it sits often rust together making it very difficult to remove the rotor to replace the parking brake shoes. I have seen that there are some aftermarket rotors which appear to have paint applied to the inside surface, but it's not entirely clear.

My question

Is there a way to make this easier to disassemble next time? Could I paint the hub surface and/or the inside of the rotor? Would high temperature anti-seize grease be appropriate here? Or should I just clean things up and reassemble as is? I had to use my biggest gear puller to get these off this time and was concerned that I might take a chunk out of the edge of the rotor. There must be an easier way...

Rear brake with rotor attached

rear brake with rotor attached

Rear brake with rotor removed

rear brake with rotor removed

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    Buff off the rust and apply thin coat of anti-seize paste. – Moab Jul 5 at 21:08
  • I found an “easy” way to remove the rotor was to stitch drill it and split it with a chisel or weaken it with a grinder and split it. Much less likely to damage the bearings etc. – Solar Mike Jul 5 at 21:27
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    @SolarMike: that's fine if I were going to replace the rotor (as I am intending in this case) but not when all I want to do is check the condition of the parking brake shoes. The gist of the question is how to avoid having to resort to that kind of destructive diassembly. – Edward Jul 5 at 21:29
  • Well if you fit new shoes when you fit rotors and don’t mis-use the handbrake, like driving it with it on, then it should easily last the life of the rotor. – Solar Mike Jul 5 at 21:31
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I always put a very thin coat of copper grease on the mating surfaces and also on the mating surface between the rotor and the alloy wheel.

Only a small amount is needed and you want to make sure that there isn’t too much that can run onto the rotor friction area even when hot.

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