[jaymd123]

So I had my parking brake adjusted a few months back because it was not holding on my driveway (25-30 degree incline). After it was adjusted under much protest because it was "in spec" I drove it off the lot and the rear brakes were dragging (I assumed from the adjustment). I was driving down the highway at about 65mph and decided I should turn around and go back to the shop after 2-3 miles. Before I could pull off the road the brakes stopped dragging and the car was smooth again.

Now, I've noticed after that incident when driving at highway speeds and I activate the brakes there is a vibration coming from the rear. I can confirm by pulling the parking brake up while driving (gradually of course) and the vibration/shuddering is more pronounced.

The shop tells me the rear rotors are warped and cracked due to the parking brake being left on while driving. Since I'm the only one who has driven my car I'm pretty sure I haven't left it on. They haven't said wether they would fix it or not yet and we've been going back and forth. Can anyone even tell me where to start with this? I really don't want to have to come out of pocket for something they did.

[The HACK]

It's plausible. If they adjusted the parking brakes to a point where it comes in contact with the drums lightly, when you start driving it the shoes "drags" on the drums long enough for it to heat up the hub and physically go out of round when you stopped the car.