Mercedes E Class (211) Estate rear suspension

[Stegel]

Hi,

I'd appreciate some advice on the (self levelling) rear suspension on a car I've just bought for my wife - a 2 year old 320cdi Sport Estate.

When parked for more than an hour the offside rear suspension lowers until the car is sitting on the bump-stops and the tyre tread is wholly within the wheel arch - the nearside suspension remains at its original level, with the arch well clear of the tyre. On starting up, the rear levels up within 20 seconds, and there is no difference in ride height.

I bought it from a non-franchise dealer, and today took it to my normal Mercedes dealer for a check. They advise that as long as it levels up on running, there is not a problem, but to me it seems symptomatic of a fault - either in the pipework or suspension unit - which I would like to see sorted while under Mercedes' warranty.

Is this normal or shall I press to get it investigated and rectified?

Many thanks

[anonymous-user]

They're fobbing you off - there clearly IS a problem!

Mine doesn't budge unless there's a load in it, then it only levels once you start up the car - yours sounds like its probably constantly correcting whatever the problem is whilst the engine is running, but once the engine is killed it stops compensatiing and drops.

Even if you didn't buy it from your local MB dealer, its under manufacturer warranty and is clearly not right - I'd push to get it fixed, they'll surely get paid for the work from MB anyway?

I assume it has full MBSH? If not that could allow them an excuse to try and duck out of the responsibility.

[mbtech01]

sounds like the o/s/r air cushion has an internal leak which gradually looses air & deflates when the vehicle is parked up. When running the suspension compressor will compensate for the leakage & ensure its constantly kept upto pressure. However this could eventually cause the compressor to overheat causing more expense. There is also another possibility that the air pipe going the the o/s/r air cushion is leaking slightly at any of the joins. A common place is under the rear seat base on the n/s/r where you'll find the air pipe from the front passing under the rear seat & there's a connector joint here which is taped up in felt tape. The pipe pulls apart allowing air to escape which in turn causes air loss to the rear air cushions causing ride height problems.
If the air cushion is faulty, its not a nice job to replace as the whole rear suspension/axle/subframe has to be dropped as the new air cushion comes complete with a resevoir tank & pipework that feed over the top of the rear subframe. Its not the best of jobs to do & my guess is the dealer knows this & can't face replacing it !
Either way you have got a problem - so get the car back to your dealer & get them to sort it !

[ClaphamGT3]

As above, if the bellows have failed, its a £3k fix. A good inde should exhaust all possibilities around pipework 1st. I had my local MB dealer tell me that the ballows had 'definitely' failed on the AAMG and want to charge nearly £4k to fix. Inde found a leaking union in the pipework and charged £110 + VAT to fix...

[Pontoneer]

Alternatively , since you've 'just bought the car' take it back to the dealer you bought it from and either insist that they fix this , or reject the car and go look for another one .

[softtop]

It does need sorting out because as the moment the pump is having to compensate after only one hour. As the problem progresses the pump will end up working harder than normal and may fail. The pipe work is not that easy to solve because the leak could be anywhere. it is worth seeing how much to replace pipes because they are so cheap and you can spend more time looking for a fault than just replacing.

On a two year old car it should be sorted. Think how it will be after you have owned it for a few years...

[Stegel]

Thanks for all the (really useful) replies, and for confirming what I thought would be the case - I'd had the car for only 24 hours when posting and it was a flying visit to the MB dealer (who has serviced my car from new, and who I generally regard well) to have the headlights adjusted for France so we didn't really discuss it in depth. Now we're back I will take up the matter further. The car still has 8 months of MB warranty left, but I have put the non-MB dealer I purchased it from on notice in case MB and their dealer don't co-operate! (BTW it has full MB service history - I found it surprising how many - well 2 out of 4 I looked at- sub 3 year old cars had already been outside the MB franchise dealers, interrupting MobiloLife, bodywork warranty etc)

Thanks again.

Edited by Stegel on Saturday 6th August 00:31

[Stegel]

Just an update and thanks again - the car has been alternating every few days from dragging its offside rear corner to remaining dead level - I half expected it to fail to replicate the fault when at the dealer. I dropped it in last night and this morning it was listing heavily to starboard, so new suspension unit on order and to be fitted under warranty.

[ColB2]

Self leveling rear suspension failure on Mercedes E class Estate, safety recall just out. MB fix recall is reference P199

[Stegel]

Thanks ColB2 - it went in last week for the parts to be replaced.

I didn't update after my most recent post - after the suspension unit was replaced, it still sat unevenly so further checks were made - the other side's unit was found to be out of alignment, so was re-seated, then all the pipework serving both units was replaced and finally the level sensors were replaced. Seemed to do the trick (hardly surprising as virtually nothing original remained!) although occasionally it looks very slightly out of level, but not sufficiently to provoke me to get a tape measure out, and the works did improve the ride, which looking back pre-repair was awful, 18" wheels notwithstanding. I have developed a habit of walking around s211 when the opportunity arises - usually in the dealer car park! - and the majority display discrepancies between tyre and wheelarch side to side.

[AC43]

Stegel said:

Thanks ColB2 - it went in last week for the parts to be replaced.

I didn't update after my most recent post - after the suspension unit was replaced, it still sat unevenly so further checks were made - the other side's unit was found to be out of alignment, so was re-seated, then all the pipework serving both units was replaced and finally the level sensors were replaced. Seemed to do the trick (hardly surprising as virtually nothing original remained!) although occasionally it looks very slightly out of level, but not sufficiently to provoke me to get a tape measure out, and the works did improve the ride, which looking back pre-repair was awful, 18" wheels notwithstanding. I have developed a habit of walking around s211 when the opportunity arises - usually in the dealer car park! - and the majority display discrepancies between tyre and wheelarch side to side.

I think this is because the system is always trying to self level. I've got Airmatic on mine so it tries to level on all four corners. If it's stitting on a surface that's not 100% level I see fairly large variations in wheel-to-arch spacing when I lock it up and walk off.

[Shamu]

ColB2 said:

Self leveling rear suspension failure on Mercedes E class Estate, safety recall just out. MB fix recall is reference P199

Thats not even remotely relevant..

[Stegel]

Not quite sure what's meant by "not relvant" but Mercedes' recall letter indicates that if the offending link is faulty or breaks it will have an impact on the ride quality and operation of the rear suspension - to what extent that is "safety related" I don't know, but cannot be insigificant if it prompts MB to contact every s211 owner.

[ColB2]

Well.... In my case was relevant, because it saved me about £4500-£5000 of repairs that became necessary since the car had gone low then very high then suddenly very, very low blowing the air bags.