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R Class Rear Suspension Air Bag Replacement

224K views 180 replies 73 participants last post by  injuhneer 
#1 ·
I just replaced both of my rear suspension air bags. My R class has the full Airmatic suspension, which I have already replaced myself the front ones last year at $1000 x 2. I found a company Air Suspension Kits, Air Shocks, Suspension Parts, Struts - Arnott Industries, which sells remanufactured suspension parts. I bought the set of two rear air bags for $299, compared to $550 each ($1100 for both rears) from MB . I installed them yesterday, and so far they are performing like OEM. The air bags are manufactured by Continental, which makes tires, and have a division which is Contitech that makes air bellows and other air suspension related parts. Arnott offers lifetime warranty, as I was hesitant because I thought their would not perform as well or that they would pop when loaded, but so far I am pleased. The replacement is so simple, as it also comes with instructions. The steps for removal are the following:
1.Raise up the vehicle from the body or rear cradle to allow rear tires to drop down.
2.Remove Compressor Fuse located in Engine Compartment (The second large orange 40 amp fuse is the compressor's). Remember to remove key from ingition.
3.Once vehicle raised from rear, removed the rear tires
4. Remove the airline at the top of the air bag on the opposite side from the wheel with an open 10mm wrench and remove the adapter from the line, as the new one already has such piece.
4. Pry the air bag down from the top with a flat screwdriver to release it from the locking pins at the top.
5.Remove the air bag by squeezing it through.
6.Remove and install the white securing pins with a flat screwdriver
7. Install the new air bag with the air inlet towards the inside. Make sure the bottom is seated properly to match the notch.
Reconnect the airline and ensure that it is all the way in and that the colored marks on the airline are against the fitting in the airbag (just push it hard until it cannot go more).
8. Reinstall tires, lower vehicle (the vehicle will drop the wheels into the wheelwells), reinstall the fuse, and turn on the car so that compressor fills the bags (you may hear a couple of pops, but they are normal).
9.Check tha the vehicle does not drop all the way into the wheelwells, as it is a sign that you still have an airleak (leaking air at the connection fitting is the most likely problem), otherwise, you are done!
 
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#3 ·
Suspension airbags replacement time

It took longer to jack up the car and remove and install the wheels as I have 22" rims on them, than to replace the air bags. 30 minutes to replace both aigbags, and about 1 hour to jack up the car, remove and install the wheels, as it is hard to hold the align the wheels and hold them in place to screw in the lugs. Before I tried bending the air suspension links from the sensors to have a lower ride, but it messed up the level, as the right side is about in inch lower than the left, and you can feel it at the wheel because it always pulls to the right, even in flat roads. I disconnected all the airlines at the distribution valve in the engine compartment, and unplugged the battery, even the memory battery under the front passenger floorboard (removed the compressor fuse as well and key from ignition). That company Arnott sells the front air shocks for MB SUV's for $499, compared to $1300 at MB. They even buy your old ones for about $50, and they pay for the shipping. Hope this helps.
 
#6 ·
Suspension airbags lifetime

I was talking to the Mercedes Parts clerk, and he told me that on all Mercedes air bags only last about 68k miles. I think that the climate conditions such as cold weather adversely affect the life as I had to replace my front ones at about 60k. I was damn pissed, because these cars are not cheap and the parts are damn expensive as well, but oh well, I wanted MB.
 
#7 ·
Airmatic system is a POS!

Other than the totally unreliable Airmatic suspension system, the R500 we've had for 4 years has been a fine car. One front Airmatic strut has been replaced at 34K miles and the other at both 34K and 68K. One or both of the rears have also failed in the 45K range (can't remember back that far). It is sad that Mercedes have become less reliable over the years. I am (so far) happy with my latest Arnott front replacement and will be ordering rear replacements from Arnott today as one or both of the rears are failing again.

If I could replace this piece of crap Airmatic system with some other reliable system I would, but it is too integrated into the car.

Anyone else have them fail so regularly?

gbooks
 
#8 ·
Suspension airbags lifetime

I don't like all the money spent repairing them, and all the hassle with the leveling, but I like the way it lowers itself on the freeway, and how it gives a better stance with 22" wheels. When we had the rain here in California, the streets were flooded, and it helped because I could raise the vehicle a few inches while other cars would get water inside their cabins. I would say that it is a close match between the benefits and the problems, and although my wife nags me for getting one with this option, I am still happy with it.
 
#9 ·
R Class Rear Suspension Air Bags Replaced In One Hour!

While I still think the Airmatic system is a POS that should have a 100K warranty from Mercedes, at least 3 of 4 corners of my (wife's) R500 have Arnott air suspension components.

A few months ago, I tried and failed to install the front passenger Arnott strut and ended up paying a local shop $200 labor to take care of it for me. One of the rears has been leaking for about a month, so I ordered a set from Arnott (only sold in sets), and tentatively went about trying to install them on my own.

I am happy to report that I was able to complete the install in about an hour! Just as clscruizer350 mentions above, re-installing the wheels took longer than installing the suspension components!

Ironically, since the time I ordered the rears, the final POS Mercedes strut has taken a dump and is leaking worse than I've ever seen (and I have seen 6 or 7 leaking on this one vehicle in the last 4 years so consider myself a professional). So it appears I will have a full Arnott air suspension system before February ends! Now if I could just figure out how to install the front strut on my own I could save myself $200 more. Any tips or hints out there?

Thanks for reading.

gbooks
 
#10 ·
If you remove minimal components to just allow tou to remove and replace the strut is fairly simple, but it is a bit harder than the rears. There is a large bolt that holds the strut fork to the axle. Then the tie rods from the rack and pinion and the stabilizing bar. There is a black plastic strap tied around the strut that holds the brake line. It is locked with a plastic pin at the tip of the tie, so you push that pin out with a small phillips screwdriver and the strap is loose, so you can reuse it for the new one. Do not lose that small pin, which is about 1/4" long, otherwise the strap will not lock and you will have them dangling. Once you have removed those parts, then you move to the top in the engine compartment. There are three nuts that hold the strut in place, 2 visible, and one inside the hub. You will need a 13mm deep socket to remove the nut that is insode the hub. But before you remove all the nuts, disconnect the airline with a 10mm open wrench. Remember to remove the compressor fuse located at the passenger side of the engine compartment (it is the large Orange 40 amp fuse to the right, as there are only 2 orange fuses) so the compressor does not turn on unnecessarily. Do not leave the key in the ignition while raising the vehicle. Once the airline is and the nuts are removed, the strut should drop a few inches, but it will not clear the well. You need to step on the axle and compress the airbag to clear the well. You will need to maneuver the fork ( turn the bottom end of the strut sideways) so it clears the driveshaft. This should allow you to clear the entire well and remove the strut out of the vehicle. If you step on the axle too hard, make sure you do not damage the level sensor at the top of the leaf, or cause the driveshaft to come out of its differential (front).If it does, just push it in with your hands until you hear a click. You should be able to remove it with little effort, depending on how you maneuver the strut. Installation is done in reverse order. First secure the top, without installing the airline until the end, so you can compress it when putting the fork in place. The tie rods tend to turn, so you will need an air gun with more than 200 pounds of torque, or an open wrench with a star socket. The big bolt is important to be tighened well, because it will rattle when driving (I learned this way), so you need to hold one end of the bolt while turning the other. This should do it, just put the fuse back when you are done, and start the car so the bag fills up.
 
#11 ·
clscruizer350, thanks for the reply. As I mentioned above, I tried this on the front once before. I had the new strut most of the way in, but couldn't get the fork over the driveshaft. I do not recall if I tried to put the fork over that before maneuvering the top into place. Maybe I can try that with the next one, or just suck it up and pay the $200 to my local independent shop knowing that I saved $360 by installing the rears myself!

In any case, I will be glad to have all four corners on Arnott Industries lifetime warranty equipment rather than the s**t that Mercedes puts on from the factory.

gbooks
 
#12 ·
I've thankfully not (yet) had any problems with the air bags, but I just got our R320 CDI back from the dealer after the left-hand rear shock absorber was replaced under warranty after failing only 10 months after it was replaced. I couldn't believe it when the tell-tale knocking from the rear started again a couple of months ago.

Thankfully we were not out-of-pocket for this replacement, but less than a year and only 10,000 miles is literally "shocking"!
 
#13 ·
rear shock absorbers needed

Hi Gents,

well, it seems that you guys bought all the rear shock absorbers they had available ... I need a pair of them since both started leaking. Oh, on this occasion: since English is not my first language but German may I ask what is the difference between "strut" and "shock absorber"? Is it not basically the same?
Just in case Arnott don't have any available what's your suggestion?

Rgds

Daniel
 
#14 ·
What a great thread, you should have post some pictures if you can. I own four mercedes-benz and I highly recommend you to buy a wheel hanger from

WheelHanger.com - The Ultimate Wheel Hanger

Mercedes normally uses 14mm wheel hanger. It makes changing tires very easy especially with the 18" wheels I have. I guarantee you will save your back the next time you change your tires! These are used by mechanics, thats how I found out about them!
 
#15 ·
Leak somewhere in the system

Hello all -

So the good news: Arnott Industries at all four corners now! And the bad news: It appears my rear airbags were not bad after all. The right rear sagged overnight before the switch and after. This means there is a leak somewhere. How can I figure this out without taking the car to a shop?

Also, I have a set of used OEM rear airbags if anyone needs some. PM me for more info if interested.

Thanks for looking!

gbooks
 
#17 · (Edited)
Easy Replacement

I am not the greatest mechanic, but that was one of the easiest jobs I've ever done. Took me less than an hour.

Perhaps it was only a leak, but if that earlier post about the bags lasting 68k is true, it was time anyway.

Hats off to BenzWorld and its members, Arnott and its discount code.

The dealership can eat my shorts.

I called Arnott and they (no longer?) take the core for $50 as posted elsewhere. What should I do with these old bags? One is still good for sure, the other may have a leak (or is bad).
 
#141 ·
Easy Replacement

I am not the greatest mechanic, but that was one of the easiest jobs I've ever done. Took me less than an hour.

Perhaps it was only a leak, but if that earlier post about the bags lasting 68k is true, it was time anyway.

Hats off to BenzWorld and its members, Arnott and its discount code.

The dealership can eat my shorts.

I called Arnott and they (no longer?) take the core for $50 as posted elsewhere. What should I do with these old bags? One is still good for sure, the other may have a leak (or is bad).
Sell it on ebay
 
#22 ·
Question on Airmatic Raising Automatically

In in 2007 R500 - When driving strictly on Local California streets - Suspension sometimes lowers and raises itself. I want driving from Highway into streets, but only in streets. Is this normal? I asked MB Dealer to check if something was wrong as usual - nothing. Could you guys help if with your experience.
 
#23 ·
In in 2007 R500 - When driving strictly on Local California streets - Suspension sometimes lowers and raises itself. I want driving from Highway into streets, but only in streets. Is this normal? I asked MB Dealer to check if something was wrong as usual - nothing. Could you guys help if with your experience.
It is my understanding this is normal. If i recall correctly, the manual states that the car lowers at speeds above 45 MPH.
 
#25 ·
Eric,
I replaced one bag in no time. And es it took longer to remove and re-install the tire!!!!!!!! THe other issue that took a little time was the airhose..difficult to get a wrench in there. All toll it took 40 mins to replace the blown bag. I will do the other soon. So, Mercedes wanted $2500 i did it for $29 plus shipping and a little sweat!
 
#26 ·
Well i want to thank who ever posted this as i have just had my rears replaced with the Arnott and including install at my local shop total cost 406.00, i had called the dealership here and they wanted 780 per unit and 1000.00 for install. Just picked up the car so only time will tell but with a lifetime warranty from Arnott and only a 2 year warranty from MB, this was a total no brainer, saved over $2,000.00 real world dollars, Thanks to all who contributed. I owe you one!
 
#31 ·
Many thanks to the OP!!!

Not to sound repetitive here, but after purchasing my first Mercedes, which is a 07 R320 CDI with 63k miles on the OD, after a month of ownership the rear passenger bag was the first and only thing I've had an issue with. I found a really good independent MB shop and they wanted $700.00 for one side only!!! After a little google searching and finding this forum and thread, I was able to purchase the replacement bags thru Arnott Industries shipped to my house for $285.00.. Ordered on Monday, received on Thursday, and after an 1 hour's work, I had both sides replaced and fully functioning like new!!!! Hats off to the OP for locating and writing up this thread... You saved many a boat load of money that I can now use for some other mods!!!!

Thanks a million!!!!!!:bowdown:
 
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