8V S3 - Strange Noise While Braking in Reverse

[Four_RingCircus]

I started experiencing a strange noise from my 2017 S3 while applying the brakes in reverse. The sound is a bit hard to describe, but it is a loud, resonating type of noise that sounds like it is coming from the rear. It is not the usual mild break squeal/clunk that often happens after first driving the car after wet weather or a wash. I initially thought it might be the diff, but the noise does not start until the brakes are applied. The noise does not return once I shift out of reverse, and the car seems to drive just fine otherwise.

I changed the rear rotors and pads in mid-December, and the car has been daily driven without issue until today. I'm at about 62K, and everything besides the rear brakes are original. Anyone else experience this, or have any ideas?

Thanks!

[Four_RingCircus]

I did a visual inspection and couldn't find anything wrong at first glance. I was hoping someone had encountered this before and could help me narrow it down.

[S3DUDE]

It is probably a small rock, piece of gravel stuck between the rotor and the brake shield. These suckers tend to slightly "give" and move slightly (rotate) minimally and the noise goes away but when you put it in reverse they turn slightly the other way and they make that hideous noise. Grab a long screwdriver, a long rod, the handle of a hammer or even a drum stick and push inwards on the brake shield. Push it on a few places and try again.

[Four_RingCircus]

Thanks for the response, you may have been right. I tried replicating the issue this morning to help diagnose, but thankfully it did not return. The roads in PA are an absolute warzone this time of year and there is loose gravel and debris everywhere. I suspect the culprit may have dislodged itself on my commute home since I last put it in reverse.

[S3DUDE]

Thanks for the response, you may have been right. I tried replicating the issue this morning to help diagnose, but thankfully it did not return. The roads in PA are an absolute warzone this time of year and there is loose gravel and debris everywhere. I suspect the culprit may have dislodged itself on my commute home since I last put it in reverse.

^^Yes sir!!! absolutely. So the noise/sound is terrible, it sounds just like the chalk on the board or like scratching a piece of metal on a rough surface. The easiest solution is to grab solid solid(bar) screwdriver, etc and push on the brake dust shield. I am happy for you that went away.