S211 E500 rear air shocks airmatic

[bolidemichael]

I have a leaking osr shock and the indy has told me that:

- a leak can't be traced i.e. to a hose, as it's essentially a sealed black box

- it differs from the standard S211 system as it has a nitrogen reservoir

- the rear subframe needs to be dropped for a replacement

- therefore we may as well replace both units together as it's 5.5 hours labour

- arnott don't offer replacements for the full airmatic system (same system as the E55)

- bilstein manufacture them for MB but are almost the same cost

- I should opt for the MB remanufactured units at a smidge under £2k with labour

Has anyone experience a replacement of the rear air shocks for this system? I'd be interested to hear of your experience. I'm happy to go for OEM, but to verify the options presented to me.

 

[bolidemichael]

Okay, so the long and short of it is:

- OEM is the way forward. There may be an option of a Bilstein unit, but the cost is similar to OEM.

- If I replace one, I replace two, otherwise I am simply duplicating the cost of dropping the subframe (5.5 hours) when the nsr inevitably fails

- It'll cost from £1,500 to £1,900 depending on the indy's proximity to London and how much time I am happy to commit to getting Magnus there

 

[E55BOF]

I presume that the indie you use has already checked the whole system for leaks and found nothing? These units often develop very small leaks at the remote air chambers on the other end of the thick black pipe leading inboard from the air spring, and this can be sorted with an epoxy putty like JB Weld.

- If I replace one, I replace two, otherwise I am simply duplicating the cost of dropping the subframe (5.5 hours) when the nsr inevitably fails

I was lucky enough to get a Bilstein full Airmatic unit on offer from Poland (where the factory is) for £400.

The subframe can be dropped on one side only - 2.5 hrs labour at a good indie like Terry Gates - so you can just replace the one. IF the other does fail, the only thing you duplicate is the inconvenience.

 

[bolidemichael]

I presume that the indie you use has already checked for leaks ands found nothing? These units often develop very small leaks at the remote air chambers on the other end of the thick black pipe leading inboard from the air spring, and this can be sorted with an epoxy putty like JB Weld.


I was lucky enough to get a Bilstein full Airmatic unit on offer from Poland (where the factory is) for £400.

The subframe can be dropped on one side only - 2.5 hrs labour at a good indie like Terry Gates - so you can just replace the one. IF the other does fail, the only thing you duplicate is the inconvenience.

Thanks - they told me that it's essentially a black box, as per my first post.

 

[merc85]

I’ve had twin arnotts fitted on the back of my s211 e55k. You leave the resvour in place so no you don’t need to drop subframe as the arnotts do away with the alloy tanks.

 

[E55BOF]

The air spring is a sealed unit; the remote chamber isn't. Both mine were leaking slightly... If the car goes down on the rear quickly, it may well be the air spring; if slowly, it could be one or both air chambers (the rear system is interconnected from side to side). If your man hasn't checked them before giving you a diagnosis, I'd be wondering just how good he is...

(My car went down quickly, and I was pushed for time, so I had just the air spring replaced, using the existing air chamber. It still went down, but more slowly, so I had the air chambers sorted. It's fine now.)

 

[E55BOF]

I’ve had twin arnotts fitted on the back of my s211 e55k. You leave the resvour in place so no you don’t need to drop subframe as the arnotts do away with the alloy tanks.

Arnott don't list replacement units for the full Airmatic cars.

 

[E55BOF]

This is interesting reading. There's no mention of a nitrogen reservoir in the air spring, though... The Definitive Guide To The Mercedes-Benz Airmatic Suspension System

 

[merc85]

My e55k has full airmatic and arnott rears lol

 

[merc85]

Arnott airbag Part number a-2725 with AMG suspension replace in pairs, we are a Arnott dealer btw

 

[E55BOF]

Doh!! I'm confusing it with the Airmatic dampers, which they don't do. My mistake...

I don't suppose you know for sure whether there's a nitrogen reservoir in the OE units, do you?

 

[bolidemichael]

Okay I'm following up on this issue. Basically, I have a huge debt of gratitude to @E55BOF as he has saved me an absolute packet.

The air spring is a sealed unit; the remote chamber isn't. Both mine were leaking slightly... If the car goes down on the rear quickly, it may well be the air spring; if slowly, it could be one or both air chambers (the rear system is interconnected from side to side). If your man hasn't checked them before giving you a diagnosis, I'd be wondering just how good he is...

I went to see Terry at Waynes Gates Mercedes and the issue was related to corrosion where the hose meets the alloy reservoir (air chamber, containing nitrogen for the air bellows). Corrosion causes gaps to appear in the union of hose to lip and hence, a slow leak ensues. They resolve it by removing the corrosion, applying steel weld, smoothing it out and re-installing, with a replacement jubilee clip.



It cost me less than £300 and I saved £1,200-£1.700 depending on if I went to PCS or kept it local.

- a leak can't be traced i.e. to a hose, as it's essentially a sealed black box

It transpires that my indy wasn't attentive enough, when I had probed them about whether it could be a leaking hose; I'm quite annoyed as to how they told me that it wasn't possible to assess for a leak but it was cobblers.

Many thanks, E55BOF; Terry says that you are one of his nicest customers and I'm pleased that I considered your opinions carefully and followed up on them! In particular, the replacement of the duo valve resonated as I had paid £450 including removing the servo and bleeding the brakes, whereas Terry's guys would've scraped their knuckles and saved me another £300+/-.

 

[bolidemichael]

This evening I'm afraid to say that the osr was sat noticeably lower than the other corners. The ground wasn't entirely level, so I have parked it on the raised setting on my driveway and measured the ride heights post parking

nsr 670mm
osr 660mm

I'll aim to leave it in situ until the weekend and see what happens...

 

[Mondayo]

Arnott airbag Part number a-2725 with AMG suspension replace in pairs, we are a Arnott dealer btw

Sorry to hear it's dropping again.
I got the Arnott airbags from Merc85 last year. Price wise there's not much in it between buying the Arnott ones and Merc ones. As when I was looking Merc were doing a cashback thing, where they have £X back for your old suspension/airbags.

I think the Arnott ones were £30-40 cheaper but the big saving, as mentioned above, was that they're apparently much easier and cheaper to fix.... although apparently mine was a bit of a pig to work on, as must bolts were very resistant to being removed.

 

[E55BOF]

This evening I'm afraid to say that the osr was sat noticeably lower than the other corners. The ground wasn't entirely level, so I have parked it on the raised setting on my driveway and measured the ride heights post parking

nsr 670mm
osr 660mm

I'll aim to leave it in situ until the weekend and see what happens...

Mine has been fine since the osr air spring was replaced and the chambers resealed. My drive is also not entirely level - slopes very slightly downwards and towards the osr - and the car settles a little unevenly if left standing. It's barely noticeable - can be as much as 20 mm side-to-side and front-to-rear - and varies depending on exactly where the car is parked. Before the osr air spring was replaced, that corner was sometimes fine, other times was very obviously down.

 

[bolidemichael]

The lack of gap on the OSR was so pronounced on the rippled surface on the access road at the rear of my garage. I haven't ruled out that this was a contributing factor but I have never seen the suspension so pronounced and of course this was on the side that was repaired.



I have measured the gap this morning and it is still sitting at the same measurements as on Tuesday evening. I'll try to not drive that car over Christmas and see if the gap changes.

 

[bolidemichael]

Well, that's that... the rear suspension has completely collapsed now. It looks as though the 'fix' didn't work and I'll have to get it down to my local indy for what I assume will be a replacement of the suspension on both sides. I can only hope that the compressor hasn't been pushed to failure, that the parts won't be too delayed as a result of Brexit and that Brexit won't have increased the costs too much.

Happy New Year 2021!

 

[bolidemichael]

 

[E55BOF]

Oh sh1t... I know the feeling too.

 

[bolidemichael]

It's weird how it completely gave up the ghost... it's as though a hose has become detached. Alternatively, the compressor may have given up the ghost, but I don't know how to ascertain this - I suppose that I'll find out with a diagnosis. Someone mentioned on another thread that it may be prudent to rebuild the compressor with an internal rebuild kit, whilst replacing the rear units.

For the sake of £250, I may not bother contacting Terry about this, unless it is something directly related to the repair work.