Rear Slammed After Sitting for Days; Raises Once Driver Door Opened
Thread Starter
Senior Member
Joined: Oct 2015
Posts: 287
Likes: 24
From: New York
2012 GL350
Rear Slammed After Sitting for Days; Raises Once Driver Door Opened
Vehicle sat for 6-days and I noticed the rear was slammed, didn't worry much about it. Had to run out last night and just opened the driver's door and waited to see if it self leveled, which it did and strangely, I didn't hear a compressor kick on. I never really noticed this before, is this normal?
Of reference, I had the both rear tie rods, both rear hydraulic shocks, both lower rear shock bushings on the control arm not to long ago.
Of reference, I had the both rear tie rods, both rear hydraulic shocks, both lower rear shock bushings on the control arm not to long ago.
MBWorld Fanatic!
Joined: Jan 2010
Posts: 3,114
Likes: 782
NGL450 w/EORP, S550
Yes this is the usual behavior when your rear airbags are at end of life. You have a slow leak on one or both rear airbags. It will try to level the car every time you open a door, using central reservoir pressure or the compressor as necesssry.
have them replaced before your compressor burns out from running all the time.
buy arnott or Bilstein brand airbags - it’s 15 minutes a side if you’re an experienced DIYer.
have them replaced before your compressor burns out from running all the time.
buy arnott or Bilstein brand airbags - it’s 15 minutes a side if you’re an experienced DIYer.
Thread Starter
Senior Member
Joined: Oct 2015
Posts: 287
Likes: 24
From: New York
2012 GL350
Thanks Max Blast. I never addressed this, but have noticed a weird occurance.
If the air suspension is in normal (non-raised mode), the rear will sag after a few days. But, if the vehicle is parked in raised mode, it keeps it height and doesn't sag.
If the bag had a leak, wouldn't it still leak in raised mode? I do agree with you and feel these bags are at their end of life, as they have never been replaced. I just found this observation strange.
If the air suspension is in normal (non-raised mode), the rear will sag after a few days. But, if the vehicle is parked in raised mode, it keeps it height and doesn't sag.
If the bag had a leak, wouldn't it still leak in raised mode? I do agree with you and feel these bags are at their end of life, as they have never been replaced. I just found this observation strange.
MBWorld Fanatic!
Joined: May 2015
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From: Allentown, PA
'08 GL 320 CDI
Depending on how the bag folds, it can leak more or it can leak less. As you drive, though, that compressor is working much, MUCH harder than normal to keep the bags inflated. As Max mentioned (nearly 5 months ago!), waiting to fix this will only mean a higher service bill as it will include a compressor, as well.
MBWorld Fanatic!
Joined: Jan 2010
Posts: 3,114
Likes: 782
NGL450 w/EORP, S550
Yeah it depends on how they sit - sometimes it sits just so and everything seals up. It’s misleading and often not enough to be considered a clear slam dunk. But when you are driving you can bet these bags are moving and leaking; and the compressor is doing its very best to pressurize them.
so you are now way behind the power curve on this, I now recommend both bags and a new compressor.
so you are now way behind the power curve on this, I now recommend both bags and a new compressor.
