2018 S Class making loud noise over speed bump
I wonder if anyone with air suspension experienced what i did on video.
It is much louder than what it appears on video in real world.
This happens only with car raised manually.
Speed bump isn't that big or sharp at all and speed was only 18-20 mph when it happens.
First time I took it to dealer and they told me the machine say no error and everything is normal.
They test drove and could not replicate same problem.
I took this video and send to service rep. then took him to my neighbor on my car and showed him what happens.
He was very surprised and I left car for them to look again.
Now technician told me I am not supposed to drive car raised on the road.
It is only for entering or exiting driveway for clearance.
Also they are telling me not to go over the speed bump over 15mph especially with car raised up.
He told me that owner's manual should state that.
I only see on manual that car will be lowered over 50mph.
Senior technician told me that every S-Class will do same thing and they are designed to behave like that so everything looks very normal.
But I can not believe that MB states this as normal and there is no fix they can do.
Last edited by akipal; May 2, 2019 at 04:32 PM.




I wonder if anyone with air suspension experienced what i did on video.
https://youtu.be/Y0GLh5QIxJQ
It is much louder than what it appears on video in real world.
This happens only with car raised manually.
Speed bump isn't that big or sharp at all and speed was only 18-20 mph when it happens.
First time I took it to dealer and they told me the machine say no error and everything is normal.
They test drove and could not replicate same problem.
I took this video and send to service rep. then took him to my neighbor on my car and showed him what happens.
He was very surprised and I left car for them to look again.
Now technician told me I am not supposed to drive car raised on the road.
It is only for entering or exiting driveway for clearance.
Also they are telling me not to go over the speed bump over 15mph especially with car raised up.
He told me that owner's manual should state that.
I only see on manual that car will be lowered over 50mph.
Senior technician told me that every S-Class will do same thing and they are designed to behave like that so everything looks very normal.
But I can not believe that MB states this as normal and there is no fix they can do.
The very concept of raising the car is that you extend the air struts to near max. Now when you run over the speed bump, the body will swing upwards and likely to the limit of the strut.
That would be the noise. More important is that driving the car over a speed bump raised isn’t smart to begin with.
The raised position is not a position that is meant to be driven in under normal circumstances.
It reduces the ride quality and suspension performance of the car overall. Hence it is speed limited.
The purpose of raising the car is solely to deal with difficult driving conditions, such as rough unpaved dirt roads in the country and steep inclines on driveways and some intersections, etc.




my car scrap easily to driveway or to most parking lot
I leave car raised for my wife

my concern is that only right side is problem and after one pop I tried to go over same spot at 40mph
speed bump is very decent and smooth
i almost don’t feel while going over
my car scrap easily to driveway or to most parking lot
I leave car raised for my wife

my concern is that only right side is problem and after one pop I tried to go over same spot at 40mph
speed bump is very decent and smooth
i almost don’t feel while going over
way" I always drive with my car in the raised position. It will automatically lower when entering highway speeds. When I'm off the highway, I raise it back up again. After shutting off the car, after about 10 Min, the car will release pressure and lower. Once the car is restarted, it will raise up again. I never have ANY clunking / knocking sounds. Tires wear evenly, car tracks straight. Go to another dealer... My 2 Cents...




way" I always drive with my car in the raised position. It will automatically lower when entering highway speeds. When I'm off the highway, I raise it back up again. After shutting off the car, after about 10 Min, the car will release pressure and lower. Once the car is restarted, it will raise up again. I never have ANY clunking / knocking sounds. Tires wear evenly, car tracks straight. Go to another dealer... My 2 Cents...
What I stated was the designed purpose of the feature for the last 20 years or so.
It is strictly designed for providing greater ground clearance when needed.
It does reduce suspension performance and would make the car less stable at speed, hence it is deactivated at speed.
In addition the car is designed to lower at speed beyond its non-raised levels (how much and when is based on the dynamic select setting). MBC will also work a bit different.
Back in in the old days, Airmatic had 2 height settings which the higher setting turning off at lower speed.
What I stated was the designed purpose of the feature for the last 20 years or so.
It is strictly designed for providing greater ground clearance when needed.
It does reduce suspension performance and would make the car less stable at speed, hence it is deactivated at speed.
In addition the car is designed to lower at speed beyond its non-raised levels (how much and when is based on the dynamic select setting). MBC will also work a bit different.
Back in in the old days, Airmatic had 2 height settings which the higher setting turning off at lower speed.
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When this happens on video car was at 20mph. and I am getting clunking noise from 17-18mph. I am not saying I have problem going over speed bump at 50mph.
It was 17-20mph.
Funny thing is after I hear popping noise then go back to same speed bump car just go over very smoothly with out any problem.
I even tried 30mph and 40mph. I couldn't even notice there was speed bump, almost

And I believe this is how this car should be
However after driving car more than 30 min or so ( I don't know what exactly is the condition to make this problem)
It makes sound again
I took it to dealer but at first they told me they couldn't replicate the problem on the road.
so I took one guy to my neighborhood for test drive and demonstrate what happens
they admitted the loud sound but they told me that is normal for all S Class
so I shouldn't drive car raised especially over speed bump
If i want to raise car over speed bump do it below 10 mph
I can not believe this is what MB dealer saying after what they heard from the car
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There is a really quick test to see if your car works as designed. Lower it to normal ride level, drive over the same speed bumps at the same speed or the fastest you can drive without damaging the car. If your suspension makes the same loud noises at normal level, then have MB fix the suspension. If not, then there is a message not to drive over speed bumps at speed in raised position.
When this happens on video car was at 20mph. and I am getting clunking noise from 17-18mph. I am not saying I have problem going over speed bump at 50mph.
It was 17-20mph.
Funny thing is after I hear popping noise then go back to same speed bump car just go over very smoothly with out any problem.
I even tried 30mph and 40mph. I couldn't even notice there was speed bump, almost

And I believe this is how this car should be
However after driving car more than 30 min or so ( I don't know what exactly is the condition to make this problem)
It makes sound again
I took it to dealer but at first they told me they couldn't replicate the problem on the road.
so I took one guy to my neighborhood for test drive and demonstrate what happens
they admitted the loud sound but they told me that is normal for all S Class
so I shouldn't drive car raised especially over speed bump
If i want to raise car over speed bump do it below 10 mph
I can not believe this is what MB dealer saying after what they heard from the car
I've almost been in an accident because I had to choose whether to tear up my spoiler and get the hell out of the way, or go slow and risk getting T-boned, and these decisions come upon you QUICKLY. It really is a safety hazard that businesses or state highway departments should be forced to correct or face severe penalties.




I've almost been in an accident because I had to choose whether to tear up my spoiler and get the hell out of the way, or go slow and risk getting T-boned, and these decisions come upon you QUICKLY. It really is a safety hazard that businesses or state highway departments should be forced to correct or face severe penalties.
It’s not meant to be driven this way on a regular basis.
But some of the roads in the US are near third world levels, so I can see the need.
Last edited by Wolfman; May 7, 2019 at 11:50 PM.
After I got the car back last night and this morning, I drove car over same speed bumper.
It just drove over very smoothly. Now it feels like what has to be like.
Thank you for you guys feedbacks.
After I got the car back last night and this morning, I drove car over same speed bumper.
It just drove over very smoothly. Now it feels like what has to be like.
Thank you for you guys feedbacks.
Great glad you persevered and got Mercedes to make your car drive properly. Good for you.
On my S550 4MC, I can isolate that the noise is coming from the LH rear strut, I’ve just ordered one from another online Mercedes dealer for about 800.00 and I’ll have it installed. Nothing is affecting the systems working ability but for 800.00, it’s worth replacing it to make the car tomb quiet again. As for driving it raised, it’s up to you. I drown out all of the white noise in the room and do what I want. Hope this helps.






The big issue with parking over the stops, even with the suspension raised, is that air suspension can fail and your whole front will be trashed. Those of us who have suffered an MB air suspension failure know how catastrophic they can be. I've had 3 in my W211 AMG.







