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Mercedes Airmatic Shock Disassembled

111K views 26 replies 17 participants last post by  idahombz  
#1 ·
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Ok everyone I finally found some time to put together the pictures and details of the Mercedes Airmatic shock assembly. I did not include the pictures showing the epoxy cracking issue around the top section of the shock. I know there is some older post showing the problem and solutions for that repair. I think it would be a great idea for someone to find that post and copy it into this thread. That way we can try to keep as many air suspension posts in this thread as possible. This will allow everyone to see questions and solutions for repairing their air suspension without searching all over the forums. We are also finalizing remanufacturing the ABC shocks at the time of this publication. Once that process is complete, I will do the same thing and post pictures showing everyone the failure points to look for when diagnosing the ABC suspension systems. I will also post pictures and details on our coil spring replacement system due to launch in another couple months. If anyone has any questions, please feel free to e-mail me directly at adam@arnottinc.com.

Thanks everyone!
Adam

1. The first picture shows you an example of a worn lower dust cover on an Airmatic shock. Once you start to see this on your shock, the end is near.

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2. The next image shows a typical worn upper mount removed from a shock with around 80,000 to 100,000 miles. A worn mount will contribute to many unwanted problems with your suspension.

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3. One common failure of an Airmatic shock is the lower piston seal. The lower seal is designed to flex and absorb vibrations from the road. Oil, dirt, and heat degrade the rubber over time causing the lower seal to fail. This picture shows an extreme failure of the lower seal. It’s not a bad idea to lift your vehicle and inspect this seal around every 20K miles or so.

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4. Now we are moving into the air spring side of the assembly. This is the part of the shock you cannot see because it’s located behind the silver aluminum section of the shock. In order to remanufacture the shock we have to machine off the can to replace the air spring. The can is then powder coated and reassembled back onto the shock during the reassembly process later. This picture gives you a sneak peek of the rubber bladder behind the can. You can see from this first picture a typical worn out air spring bladder. The hole in the air spring is the reason it failed.

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5. Now let’s take a look at the inside of the air spring's bladder. In order to see this we have cut the rubber bag open with a knife to expose the wear spots. Once inside, you can see the vertical wear spots that happen over time. Because the air spring is made from a very thin single nylon cord layer the vertical weak spots or lines you can see on the air spring's surface will eventually pop through causing a complete failure.

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6. The last picture in the group shows the new air spring we use in the remanufacturing process. Unlike the OE bladder, we use a 2 ply design that prevents vertical wear points. You can see from the picture our air spring bladder is over 2 times thicker than the original bladder.


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#2 · (Edited)
Here is one pic of some evidence of leak

This is one picture posted (Thanks to gixxerblack), showing cracks near the perimeter of the mastic. The cracks may also appear in other areas of the mastic; I have seen a set showing them extending straight out from the brass valve.

Cracks in the mastic, which is a vibration damper for the thin neck of the brass valve, tends to show a leaking seal beneath the mastic.

The second picture shows an older strut top, before mastic was used (Thanks, benz_addict); some techs omit the mastic as well, when installing the upper seal replacement kits.

Soapy water can be used to verify leaks in either type.

A great deal of information on leaks, repairs, and a DIY top seal discussion are at the Airmatic section of http://www.benzworld.org/forums/w220-s-class/1508080-w220-s-class-owners-start-here.html. However, as Arnott's post makes clear, strut problems can and often do go beyond the upper seal.
 

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#7 ·
The warranty covers the entire shock for as long as you own the car. The warranty is good to the original purchaser of the part though. It is not transferable. If the part fails during the time you own the vehicle, we will repair or replace part at no cost. This covers everything on the shock including the electronics.

Thanks
Adam
 
#10 ·
Yes, we are planning on making the coil spring kit for the ABC cars. It’s a bit more difficult due to the fact that the ABC cars do not have sway bars. We are however working away at it and still plan on having something by the end of the year. I will definitely keep everyone posted on that.

Thanks
Adam
 
#9 ·
Great post. Pictures explains a lot.
I just replaced ball joints and both control arms. Car runs so much better but still not like it should be. It has 120k miles and the shocks look like the originals. So I bet the top mount is shut.

what about rear shocks do you have any pictures, would be interesting to see what the insides looks like
 
#15 ·
The front driver struts start to make squeaking sound when driving slow on bumpy road service. But my airmatic system is holding really good with no warning. I did replaced the air seals about 2 years ago.
Adam, Is those squeaking sounds due to lower chamber of the struts has lost hydraulic fluid ? The car has been 10 yrs old and accumulated 83K miles and I am the first owner. Those sounds is exactly like a old suspension system sounded in a old vehicle.
 
#17 ·
Air suspension replacement

I know that I am jumping in on an old thread, but I was hoping the desire for rear W211 replacement suspension parts was still alive.

I cam out this morning to a sagging driver's side rear on my 2003 E500 non-4-matic MB. The car goes level within 2 minutes of running, and takes about 4 hours to leak back down on only the driver's side rear.

It has 117,000 miles on it and this is the first occurence of suspension issues, I suspect the rest will follow shortly, seeing as 100K is about the life expectancy.

Here in Guam we have only one ASC certified MB experienced shop, I have an opointment in the morning to have them look at it.

I am looking to replace all 4 corners with the Arnott airmatic suspension replacement (coil retrofit) or an airmatic system for the front and rear.

Anyone hear if Arnott has the rear air system online or the coil replacement system up for sale yet?

Thanks

David
dunnman99@yahoo.com
 
#18 ·
I am looking to replace all 4 corners with the Arnott airmatic suspension replacement (coil retrofit) or an airmatic system for the front and rear.

Anyone hear if Arnott has the rear air system online or the coil replacement system up for sale yet?

Thanks

David
dunnman99@yahoo.com
David, a quick jump out to Arnotts website will answer both of your questions, here is a direct link to the 2000-2006 S Class w/Airmatic, w/o 4matic options: MERCEDES-BENZ Air Suspension Parts - S-CLASS 2000-2006 (W220 w/ AIRMATIC, wo/ 4MATIC)
 
#19 ·
Shock and suspension availablility

Mike,

Thank you for the input, but unfortunately I don't have a W220 (s-Class), I have the W211 E-Class.

I don't think the suspension for the front is interchangeable, at least the microfiche and .pdf I am looking at make them look different.

I had heard Arnott was releasing their E-500 (W-211) version in mid 2010, so I was checking if maybe it just hadn't made it online yet.

Thank you
 
#20 · (Edited)
DOH! my bad... coffee has not kicked in! I get stuck in a rut that if you post in the W220 forum you must have one.

Shoot them a note off of thier contact link or give them a buzz, they are real responsive and have great products.

Good luck and hope you get it sorted out. - BTW I was stationed up at Anderson back from 88-91... LOVED Guam. :)
 
#22 · (Edited)
dunnman99,

The link mjd provided to Arnott's had additional links to MERCEDES-BENZ Air Suspension Parts - E-Class 2002-2009 (w211 w/airmatic, wo/4matic) - there are Arnott FRONT struts for the W211. I don't know if there are rears yet. Things change rapidly, you might contact them through the site.

I was at Andersen too, many times - 3 ARC LIGHT tours in B-52s, and passed through it on a Constant Guard IIC deployment and while deploying to Viet Nam as a FAC. I flew 0100, the B-52D Arc Light Memorial, that is on display there, a time or two.

Unfortunately, I was there without a car at all. The island could have been a delight, if only we could have gotten around more easily.
 
#23 ·
Yeah know what you mean about no transportation there. I fell in love with Tarague beach and cans of beer instead. Crewed KC-135, 58-0093 (SAC). Had the ARC 58 Long wire Antenna for HF Radio, so I got to travel frequently over both Ponds... Took an IG Team into Andersen and Kadena AFB and kicked off an ORI at each base. Needless to say we weren't very popular on those trips. I was actually stationed at Carswell AFB during my tenure.
 
#26 ·
Yes there is a DIY



After looking at the DIY on the Arnott Website (link is posted on this thread) it does not look very difficult to me. I would say 8 out of 10. 1 being changing a tire and a 10 being changing out your transmission. The DIY is excellent. You just need to be able to lift your car and stabilize it completely. If you can not do that do not attempt this.