Contrary to others opinions, I have had "shaking braking" from a rear rotor.

It had a thick ring of rust build-up about 1/2" wide around the inner rotor diameter (right next to the "hat"). But being on the back side, it couldn't be seen till rotor was pulled. A chunk of that rust ring broke off, leaving a gap that would catch the pad every revolution.

I found it fairly quickly but only because I'd just found the same thing on a front rotor on the same car. Fixing that one reduced the vibration, then pulling the rear rotor and chipping that rust ring off eliminated it.

Yes, new rotors would have fixed it too, but this was lean times.


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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.