Hey all. Has anyone dealt with stubborn squealing/scraping noises coming from the parking brake? Noise can only be heard with windows down and driving next to a curb or other cars.

Rear brake rotors and pads are new (about a month old, <1k miles). Independent shop performed the brake work and I took the car back to them twice to eliminate the noise. On the second visit, they bent back the dust shield because they thought it was scraping.
Noise seemed to disappear but came back with a vengeance about a week later - it was so loud, I could hear it with windows up. The noise stopped when applying the parking brake at parking lot speeds, so I asked the mechanic to evaluate the parking brake. The noise stopped the next day, prior to the third visit, so they couldn't find anything. This was about two weeks ago.

Well today, the noise came back. Once again, it disappears when the parking brake is engaged but immediately returns once the car automatically disengages the brake (since the car is moving). Has anyone encountered this? I assume the parking brake just needs adjusted but I'm pretty frustrated by this car and wasting my time with local shops.

Car is an AWD base 2017 with 70k miles and in otherwise outstanding condition.

 

I had the same issue recently and bent back the shield and the noise went away for now...

 

I'd check the backing plate again. If that doesn't fix it, maybe check the shoes inside the rotor. I've never seen them come apart in a GS, but have in other cars. It's possible something is moving around in there.

 

Thanks guys. It ended up being broken parking brake shoe hardware. Parking brake was moving around and not fully releasing, causing drag.

A second shop was able to properly diagnose and repair...finally.