[Nils Decker]

I just purchased a used GL450 from 2011.

Now and then, the car makes a notable hissing sound. It sounds like it is coming from the front-right suspension. It is like air being blown out (think tire that has hole).

Is this normal? I tried reading up on it and heard that the GL has some sort of "balancing" function keeping the car straight, but I could not find conclusive answers. It seems to happen more often when breaking.

 

[RedMercedesGuy]

Could be something similar to the air suspension in my Land Rover where it blasts out air (think air brakes on a semi) after the compressor has leveled the ride.

 

[Michael Pillay]

I have an older GL450. It makes the same hissing noise as it lowers when the vehicle is shut off.

 

[ChrisD]

The next day is the car lower on that particular side ? If so the bag could be leaking until is folds over the hole.