Rear Rattle: Likely cause could be the parking brake. Affects R230 and others.

[sausage]

Hopefully this will help someone else.

I recently bought a R230 and after a short while realised that there was a very annoying rattle at the rear. MB looked at the car, and could not find anything wrong.

Searching the internet for a rattle on an R230 leads to lots of discussion about the fuel tank - it seems pretty easy to test this, "does it sound the same with a full tank vs a near empty tank"? If not, then I suspect there is a reasonable chance it is not the cause. Further still, the MB service manger said that the issue with the baffles coming loose in the fuel tank creates a sound that is more of a "thud than a rattle".

I later watched a youtube video showing how the retaining spring in the rear park brake assembly on an MB can fail and cause a rear rattle.

So, the next time I was out in the car driving over a bumpy road that caused the rattle, I deployed the parking brake one click, and the rattle stopped. I tried a few times, each time with the same results. That to me seems a very strong indicator that the rattle is being caused by the parking brake assembly. I wish the MB technician had thought of this at the time.

My local indy said it would cost "pennies to fix".

 

[SL63 Mark]

Yes it is the parking brake. It is well documented, and very annoying. I have had the same noise, only audible with the roof down. I still get is occasionally. Just ask on here, we will tell you.

 

[sausage]

The rattle is now resolved and it was the parking brake assembly that had failed and caused the noise. A cheap and quick fix that has transformed the driving experience. Parts were about £30.