Afternoon All,

I have a 2013 SL63 with 36k miles on it. The car occasionally makes this squeak/tone from the rear left side. I have found one owner who had similar (video from them attached). I have tried to contact them but they have not come back to me.

Notes of the noise:
2013 SL63 with ABC
Tone is intermittent and occurs at any speed but never heard it when stationary.
Happens with roof up or down
The tone doesn't change pitch or become more pronounced with speed or bumps in the road.
At first i thought it was brake related but seems to happen both on and off the brakes.
I thought maybe a wheel bearing, but i would expect the tone to change with speed/load.

Very odd noise and very hard to diagnose. As myself and another member had the noise I wondered if anyone else had it and knew what it was!

Thanks,
Sam

 

Do not know if this applies to your year but may help.
https://mercedes-abc-drive-carefully.blogspot.com

 

I found that article yesterday. It is very useful and goes into a lot of detail about the system. Thanks for linking it, someone has put a lot of work into that! It is specific to the early generation of ABC (R230) however I suspect the layout and the way it works are very similar on the R231. I have found this XENTRY document which describes what is happening with my car. It says to replace the pressure return valve on the front valve block. The noise is definately from the rear left, but that is not to say that chaning a component in the front valve block might be the solution.

https://static.nhtsa.gov/odi/tsbs/20...62829-2280.pdf