Rear brake scraping noise (Please help!)
 

Hi FT86 Friends - I'm in need of some help here on my 2013 BRZ. I bought the car new and it currently has about 45k on it. I'm getting a speed-dependent scraping noise coming from the rear wheels whenever driving and during all conditions. I'm posting a couple of videos. The first is spinning the wheels at all four corners of the car (bonus points if you can help with the passenger front scrape). Drivers front is silent. Pass front has a little noise but is pretty quiet. Get to the rear and you can hear the racket these are making. The rear brakes are original.

All four wheels: https://youtu.be/0zfIonYr2fw

Next, I took off the rear pads from the drivers rear. Still making the noise: https://youtu.be/x-OhNzJDBl8

I took off the rear caliper carrier and the noise pretty much disappeared at that point when spinning the rotor. There was no debris or anything between the dust shield and rotor, or any other noticeable issues. Is this related to the parking brake mechanism? Where should I begin with this?

ever use the paring brake to stop? probably not. i would make a few parking lot passes where you gently pull the parking brake-- it's still a pad/brake surface that is barely used, so if there's a buildup of surface rust at all, it's going to make noise.

also, the manual calls for brake fluid to be swapped out at 30k. have you performed that service?

No, I never use the parking brake to sop. I will give your suggestion a shot. Yes the brake fluid is flushed regularly. Thank you!

Yep, I agree, it does sound like the parking brake shoes dragging.

A few long hard stops using the parking brake may seat them/drag off the high spot(s) so they don't make that sound.

Back in the day, with drum brakes, it might have been that the return shoe spring slipped off or broke.

i thought id seen it all, until the 86furom powers that be, recommended someone go do sweet handbrake drifties to fix you car.
only other thing i can think of, is if you cnahged your pads lately, did you change the thin little retainers at the same time? those are easy to bend. i believe theyre purpose is noise/vibration reduction. i paused the second video at 8 seconds and it looke theyre in place

I hope that was a joke because that is not what was said.
Slowly stop the car with the e-brake, not rip it.

If the rears lock up, you're doing it wrong.

The rear pads are original, and I only took them off briefly to inspect.

Don't think they said that. Since it is the rear then there could be some build up on the parking brake shoes. A slow speed application of the parking brake may well clear it up. If nothing else it eliminates it as the issue.

Rear has shoes as well. Much more difficult to inspect. See above for what to try.

if you took off the caliper mount bracket and the noise went away. that leads me to believe maybe the hardware that the pads sit on may be crooked. or just need to be replaced. i’ve seen those cause problems as a toyota tech