ska597

So I couldn’t get the car to reverse out of the garage this morning. The parking brake should not have been engaged unless it does so automatically and disengages once the car is put into action Essentially I put the car in reverse and it wouldn’t back up, so I gave it and some gas which resulted in a loud and uncomfortable thud from the ? transmission or ?driveshaft and eventually the car ended up reversing.

Upon reversing out of the garage, I felt like there was some grinding going on from the front end and some vibration from the pedal once I put the car in drive. A little bit concerned about what this was. I was able to make it to work okay and I think the car seemed to drive better once I started picking up some speed, but I’m concerned nonetheless.

could it have been the parking brake which automatically engaged and was not disengaging upon reversing? While this has happened before, this was a more drastic sounding incident.

Any other thoughts?

bobblehead

did you wash the car prior ?

ska597

I did. And I hadn’t driven it since I washed it on Friday. Is this related to the issue?

bobblehead

It is highly likely as any water will create rust spot on the disc surface and in between the pads too. So, once the car wants to move, the breaking of the rust can create a loud thud.

Next time when doing washing, at least drive your car out for a few blocks and making some intermediate stops to ensure all water are off the brake rotors and pads.

Gsav

Spot on. Very likely your issue. Happens all the time to me after a car wash and each time is jarring

Sunbeltgolfer11

My 2021 E63s does this if I wash it and park it overnight. Scared the Bejesus out of me the first time it happened. If I remember to use my blower on the rotors and around the calipers to dry them a bit before covering the car it does help, or eliminate it.

Keith66

I'd just like to point out the awesomeness of this forum and everyone sharing information.

Otherwise this would probably end up with a trip to the MB dealer where they would most likely just keep replacing parts until you run out of money which IMO is what they're best at.

So thumbs-up y'all!

HBerman

Alternatively, just release the parking brake until the car is totally dry after parking.

ska597

Thanks for all the replies. The damn sound scared the hell out of me. I started thinking a lot of frightening thoughts. I’ll test it out again after work and see if it’s all cleared. I did notice some rust/film on the rotors likely due to the wash from Friday. Next time I will just dry it before parking it.

Gsav

don’t be alarmed if it still happens after a car wash even if you dry the rotors with a leaf blower or metrovac. Only sure fire way to prevent it is driving after wash and using brakes enough to get rid of the superficial oxidation on the rotors.

E634Me

Or have a car with CCBs

W205C43PFL

You can do that by pulling the parking brake before turning off the engine, so it won't engage.

W205C43PFL

It is also a problem if parked during a rainstorm or even light showers.

so... CCB FTW!

ocdbroker

Mr. Bobblehead knows what he's talking about. This happened to me once and it took me a while to figure out what happened exactly as you described. Always, always go back and forth in your driveways at the very least applying a little braking pressure to dry off the discs.