RickyEarl

Long story to read, so I appreciate it if you make it to the end.

This past summer I had both rear airsprings replaced on my 2005 e500. At the time it had 86,000mi. It now has 90,000. Have since had a falling out with that mechanic for other reasons

Anyway, I took it into a local indy who has a reputation for being persnickety to have some front ball joints and tie rods checked/replaced.

He called about 30 minutes after I dropped the car off. He said he wouldn't do the job because "this car has been butchered." He said it over and over again, very animated. He was actually mad about it.

So I went to his shop and he put the car on the lift. The "butchery" he noted was with the rear airsprings. My car has the older style airsprings with the large canister/bottle (looks like a silvery metal canteen) in between them. Hoses about the size of a garden hose run from that canister/bottle to each airspring. Apparently newer models don't have the canister thing.

The previous mechanic had used the newer style Arnott airprings and retrofitted them, bypassing the canister/bottle. You could see the ragged ends of the garden hoses up in there hanging loose. Persnickety mechanic said this setup wouldn't work with my car because the new springs wouldn't be able to calibrate and would stay overfilled.

He then said the airsprings had clearly stayed overfilled because each one was bowed out rather than straight (the baffles were bent out to the side) when hanging from the lift. They were both rubbing the shock/strut next to them, which is causing a noise on bumps. The persnickety mechanic said they were permanently "bent" and would have to be replaced.

At first I was totally buying in because of my strained relationship with the previous mechanic, but after a while this started to seem more like a perfectionist critiquing a practical job. Persnickety guy wanted more than 2X what the prior guy wanted to replace them, too.

So, am I fine? Rear end rides fine other than a not very loud squeak on large bumps. I'd like to just get the front end done and move on down the road, but I am having thoughts of selling and buying a C207 convertible too. So if I'm in for another $3K plus of repairs I'll just get rid of it.

Thanks!

mishar

You should take a picture. It would explain much better what's wrong.

That rubbing is definitely not good, but overfilling air springs is BS. If they are overfilled your car would be as high as it gets and suspension wouldn't have any travel. Anyways it's not good practical job. I would replace it with original parts. Refurbished of course.

kajtek1

You might want to talk to Arnott, but from what I read their air bags are design to work without the air tank/accumulator.
That has to make for stiffer suspension, but owners who did it did "not notice" it.
Anyway, from your description whoever replaced the bags, did not delete the air accumulators and stuff a rug on disconnected hoses. I bet that looks funny.
If the bags rub, that is another story. That not suppose to happen and you might want to contact Arnott bags installer for it.
How about some pictures?

cmriv

Tisk tisk, its hard now a days to find someone who does good work. This is a case of the indie shop woes. Bet you whoever did install them lowered the vehicle entirely vs lowering it a little on the ground, and then starting the car giving the bags breathing room to properly inflate.

In all honesty-if i saw all those un-used parts just hanging up there near the subframe i would also be bitter/upset. That kind of stuff is what a hack job does. It is okay that some people take pride in their work and there are others that don't/care-less. If he was smart he would of charged you bare minimum to remove the accumulators and sent you on your way to arnott-you'd be happy, he'd have one more customer in the books also!

RickyEarl

Thanks everyone for the replies.

I'm going to have a hard time taking pics now - should have done while it was on the lift. Best I can say is that, if you know what the airsprings look like, looking at them from the rear of the car the baffled plastic/rubber section is bent a bit to the outside of the car on each side - not all that much to my eye, but enough to be just barely touching the strut. Persnickety said that if they are bent like that while on the lift without pressure on them they're ruined, and that when the car is on the ground they'll be bent a lot more and actually press against the strut.


This is 100% what I think was done and exactly what Arnott told me. I don't notice any difference in the ride in the rear at all.

The only reason I'm even concerned is that I don't want the airspring to spring a leak (pun intended) from rubbing the strut. But I honestly don't know if they're rubbing or just touching.

It does look like a hack job when you see it, but the more I calm down and think logically, the more I think it may just be lazy rather than messed up.

kajtek1

What you see outside is just plastic cover, while the bags hide inside.
Meaning don't worry if the ribs on the cover are slightly bent, but make sure main bags are not rubbing anything.
I would drive the car on 6" blocks (or one side on high curb) and take lot of pictures by sticking hand with camera under the car. This way you will see how the bags work with normal working inflation.

mishar

Difference comes with load at the rear axle. Put three people and luggage in the trunk and it will become stiffer. Those additional tanks are not accumulators. They are extra volume that makes ride smoother under heavy load. Connections open and close depending on load.

Shadow5501

Sounds like you got the standard Arnott repair, which is fine. The whole point is to get the car back on the road without asking the customer to spend $3k on parts and labor for a set of rear factory air struts on car that is worth maybe twice that.

Care to name your mechanics for those of us in DFW? Is the persnickety one perhaps located on Davenport Rd.

wjcandee

The persnickety one is a douchebag.

The stupidity of the MB design is that the reservoir thing is hung with a hose that goes over to the spring through part of the undercarriage, and to fish it out you have to remove the whole undercarriage. The Arnott solution DOES NOT use the separate reservoir; it's built into the spring unit, which is part of the genius of its design. The OLD Arnott instructions told you to remove the undercarriage, fish the MB-design reservoir thing out, then reinstall the undercarriage, then just stick in the Arnott and hook it up to the hose, then remount the wheel. In other words, a huge amount of labor to get the old thing out, then 30 seconds to install the Arnott. The first time I watched that step-by-step video, I kept thinking that they had forgot to show you when and how to install the Arnott spring, because the first 95 percent of the video is about dropping the undercarriage and reinstalling the undercarriage, then it gets to the end and as the last steps they shove their spring in and remount the wheel. I'm not kidding.

After the switch to Arnott, if you ever needed to replace it, remove wheel, remove old Arnott, install new Arnott, reinstall wheel, done. One of our members here installed the Arnotts himself, and just left the old reservoir in. He cut the hose, tied it in place so it doesn't get caught on anything, and left the dead reservoir in place, because while it doesn't do anything anymore, it isn't going to hurt anything to just sit there. As I was within a few months of replacing the rear springs, I emailed Arnott to ask them if this was an approved way of doing it, and they kind of said, "Holy crap. You're right." They sent me a nice email that said it was completely an appropriate way of doing it that saved hours of labor, and in fact they promptly CHANGED their written instructions (and said they were going to change their video) because there was no reason to fish the old thing out. I still have the email somewhere.

Anyway, your guy is a prima-donna douche. I would avoid anyplace that gets this excited over stuff. He may be right that the workmanship wasn't great or something, and he may really, truly believe what he is telling you, but it's just unprofessional and revealing of an attitude that you don't need. There are plenty of great places to get an MB fixed in Dallas that aren't going to be such babies about it. I completely agree with Shadow in the post above -- to put a finer point on it, you're not RESTORING a VINTAGE car to like-new condition, you are REPAIRING your nice older MB so it continues to function reliably as transportation.

I love love love our E500. There's nothing about the way it looks, drives, handles, etc. that I would change, so I see no need to spend $100K to replace it. As long as I can affordably keep it running, I will keep driving it. And after 130K miles, having recently replaced the rear springs and shocks and some other suspension stuff, truing up the wheels, and otherwise keeping it well-maintained with good aftermarket and OE parts, it drives like it did the day we bought it. But when I needed a new axle, if I bought the $1200 MB one instead of an excellent CVJ Axles of Denver remanufactured one, for example, and followed that strategy all the time, then keeping the car running would be a poor value compared to leasing a new one; I would be spending almost as much to keep the old one running as leasing a new one, and that would be stupid. As it is, with my fabulous, reasonable Indy and good sources of parts, the value proposition still dramatically favors keeping the car that I love. Use Partsgeek.com (for aftermarket parts) and Huskerparts.com (for OE parts).

One thing you do want to do is find an Indy with the STAR to calibrate the height. If it looks fine and rides fine, it's probably fine, but it takes literally a minute to calibrate everythign with the STAR.

mishar

Are you sure there is additional/variable volume inside Arnott air spring? Do you have some drawings or pictures of it?

kajtek1

I think he read sale pitch about fitting 2 liters of beer in single 1l mug.

wjcandee

You can always ask the guy from Arnott that posts on here.

Bottom line is that I have them and to my surprise they transformed the way the car handled after putting 125,000 miles on the old ones. I have run them under minimal load and heavy load, and they work great. Any discussion of the Bilstein design being superior operationally is completely-theoretical because the actual Arnott product works great.

And the Bilstein design, as many things Mercedes, is completely-nuts for a part that is going to have to be replaced a couple of times during the life of the car.

mishar

I hope that Arnott guy will kick in with some additional information. This tread is in his domain.

I can't say if the Bilstein design is superior without knowing Arnott design. If it doesn't have additional volume Bilstein is superior. All other cars have similar design. Problem with additional volume is easy solvable. It doesn't have moving parts so there is not need to replace it. Just the air spring. There are aftermarket springs offering exactly that.

By the way, Toyota Camry works great too. It's just not Mercedes.

kajtek1

Technically the additional reservoir/accumulator has to have the same effect what is riding on lifted suspension.
We just had other topic about lowering and turn that understanding law of physics is not that easy.
Anyway, without the additional tank the bags will be firmer, giving less suspension travel on bumps. The difference has to be subtle and wagons don't have those tanks at all.
I drove sedan with full airmatic only for short distance, so was not able to tell if my wagon is stiffer. Than you don't expect super smooth ride from a wagon, but I put low profile tires on it and regardless having terrible roads here, I can't complain.

bbirdwell

When installing rear air bags, the rear swing arm should be raised to approximately -1.2 degrees camber (per Mercedes instructions) then air bag inflated. Failure to do so can result in damage or destruction to the air bag. The car *must not* be fully lowered onto its suspension without inflating the air bag first! Doing so can also damage or destroy the air bag. ...sigh... So...car must be elevated, a support placed under the swing arm, bag inflated, then the car can be lowered to place its full weight onto the suspension.
If the air bag expands to one side at full suspension extension on a lift it *might* be of concern but it might not. The time to check it is when the car is on its wheels. If the air bag rubs with the suspension loaded, I regard that as a problem and a potentially serious one.
I'll post next week but today was spent installing an Arnott air bag and KMac adjustable bushing on one side of the rear of my E55. Not nearly as easy as instructions make it out to be (the KMac, not the Arnott). FWIW, I had to use a Dremel tool with cutting wheel to cut off the factory installed hose clamps between the air bag and the external reservoir, then patiently and carefully sliced off and removed the original hoses that connected the stock air bags and the stock external reservoirs. I will remove the now not-needed external reservoirs.
I will have to finish the job next weekend but I'll have a full writeup with photos.

kajtek1

That is MB overcaution and I can testify that is not the truth.
Had air system frozen overnight and when I start driving at 6 AM in 12F weather the computer would dump air that bags did hold and I was riding with no air having about 800lb cargo in the trunk.
Having no other choice in the middle of Nebraska, I drove about 25 miles that to nearest city, where I could log on the net and learn more about the issue.
The system defrost itself in the time and 2 years later the bags still hold the air on car park for a week.
If 25 miles of driving with heavy load on empty bags did not destroy them, don't think lowering the car for few seconds will.
But to be safe do what manufacturer advise.

cmriv

Strange- because i've destroyed 2 sets of bags by lowering all the way, in the beginning days..... I speak from experience-not mb "overcaution"....

mishar

What exactly happened to those bags?

cmriv

the bag looked blistered. Specifically the ridges or lines on the bag. It happend twice-both times on wagons. They also didnt inflate properly. Lastyly the bag itself was rubbing the shock, which probably wouldnt be bad without the other obvious issues. Never again has that happened. Same drill for Airmatic struts on 164/251 chassis.

Lowering it all the way, to me, seems sort of suspect. Till this day i ask myself why i did that-it just doesnt seem logical at all imo. Some people may of never had a issue with it however i did. Never again.