TomS

I noticed something for the second time yesterday. It seems that after the car is washed, if I backup, I hear a what I would have to call a grinding sound. Both times I thought I had the brake on, but I checked that. I pulled forward then backed up again and it did not happen.

I have not confirmed it has anything to do with washing it (such as water on the wheel), but I was curious if anyone else has heard this.

Thanks

AppleFan1

Tom, I don't think I have heard a grinding sound, but mine is more of a squeaking sound. I will be on the lookout and pay more attention when I back out of the garage. I will let you know.

kurt benz

Mb is aware of problem and have released a updated front and rear pad set. Their sales manager's car had exactly the same problem and MB decided that the correct fix is replacement of all 4 brake rotors and pads.

jrpisha

My BMW used to do this too. After washing, the rotors on my 550i seemed to get covered with a light layer of rust/corrosion in the matter of 30 minutes or so. A short application of the brakes was all that was necessary to scrub off the offending rust & eliminate the grinding noise.

A minor inconvenience. Wonder if your issue is the same...

DaveVY

I noticed a sound like this once on our 2014 S550 and assumed it was the brake pads. One quick cycle of the brakes and no more sound.