[daelias@outlook.com]

I have the same noise on my M2 only very intermittently. It scared the heck out of me the first time I heard it, BUT I remembered having a rented car on a trip and I thought something was coming apart with basically the same noise. Turned out to be a rock stuck in-between the heat/dust shields and the rear brake disc. AND, I believe that is what you are hearing on yours. I asked my dealer and of course the car wasn't doing it when I was there, but he did offer that there was a recall on the M4 for ill fitting rear brake heat/dust shields causing a noise like I had described.

[GoSlow2GoFast]

Originally Posted by Mike01ci

I got my car back from the dealer last week (it needed a bunch of stuff). Car has 6,500 miles on it, production date 2/19/16. It is a manual.

I complained that I heard an intermittent noise (it sounded like the aluminum cans dropping like everyone described on here). The dealer told me they couldn't replicate it.

Fast forward to the next morning and the sound has multiplied.

Anyways, should I have this thing flatbeded to the dealership, or is it fine getting another 10 miles on it?

First two videos definitely sounded like the sound when small pebbles get caught in the inboard brake shield in the rear, which happens more than we'd like. It's a scary noise but isn't causing damage.

The last video I didn't hear the brake shield noise as much, but it was hard to isolate what noise was not normal. There was some road noise there, etc. But if they found metal filings in the diff then that's probably not good.

Just FYI, either of these problems, stones in brake shields or rear diff failures, would not make noise when stopped. Not sure if I read that you still heard them then, or if you meant you heard them with the car rolling but in neutral, which naturally could be true.

~gs2gf

[Mike01ci]

The diff was replaced on Friday. The noises are completely gone.

However, I only drove the car from the dealership directly to the airport where it sat until a few hours ago (30 miles total). I will let everyone know if the sounds mysteriously come back.

[Mike01ci]

Originally Posted by GoSlow2GoFast

Just FYI, either of these problems, stones in brake shields or rear diff failures, would not make noise when stopped. Not sure if I read that you still heard them then, or if you meant you heard them with the car rolling but in neutral, which naturally could be true.

~gs2gf

Sorry for the confusion. There was no noise when stopped. I was just responding to the person to told me to put it in neutral.

[rpps]

Originally Posted by Mike01ci

The diff was replaced on Friday. The noises are completely gone.

However, I only drove the car from the dealership directly to the airport where it sat until a few hours ago (30 miles total). I will let everyone know if the sounds mysteriously come back.

Glad to hear the noises have ceased. Keep us updated and good luck!