S212 self-levelling rear suspension- quick query.

[milleplod]

Having just sold my 280CDi Sport, I've found a very nice 2011 S212 350CDi to replace it.
The owner tells me that the rear suspension drops 'more than an inch' overnight. The indy who's looked after it for the last few years says STAR shows no faults.
Should the rear drop by any amount overnight? If not, should there be a fault code stored?

Pete

 

[Will]

No, it shouldn’t drop when parked overnight.

Suspect a leak, usual culprit is rear airbags.

I respect the honesty of the seller, but you need to budget for this work - on the plus side if you get it done now it should prolong the life of the compressor etc.

I’d knock a grand off. There’s pattern parts available but genuine air bags will be around that amount, plus a few hundred for fitting depending on where you go (say 2-3 hours labour?)

Small leaks in the air suspension often don’t trigger fault codes.

 

[milleplod]

Many thanks for the reply Will, it confirms what I was thinking. It doesn't put me off the car, far from it, but obviously it needs factoring in.

Pete

 

[ChrisHGTV]

Many thanks for the reply Will, it confirms what I was thinking. It doesn't put me off the car, far from it, but obviously it needs factoring in.

Pete

I’m just going through a few issues with mine. I’d suggest budgeting a bit more than a grand. I’ve had two airbags, air lines and a leaking compressor (I replaced the valve block as it’s relatively cheap and removed it from suspicion). Mines not leaking now, it doesn’t drop at all, but now I have a suspected sensor failure. So far I’ve spent about £1500 With a respected Indy And a further £500 (for one bag) was covered under warranty. In my case I had leaks in one bag at least, the compressor and the air lines. PITA doesn’t come close and I knew the suspension was likely to cause some expense. The main problem can be identifying where the leaks are. It’s probably worth checking the ride height sensors as well, the newer/replacement versions have a metal arm rather than plastic. Mine has had one replaced in its life though before I bought it. It’s a great system when it works but can be expensive and irritating to fix!

 

[Will]

I never said to budget a grand, but to knock a grand off. That’s the approx cost of a pair of genuine MB airbags - fitting of course is extra.

My logic is that of betterment - the air suspension should be viewed as a consumable item, the components age and need attention now and then (and to be fair, steel springs corrode and break on non-airmatic cars)

But to expect an older car to come with brand new MB air suspension for free is unrealistic - so if you get £1000 off and it costs £1200-1500 all in, it’s not a bad outcome if the OP likes the car and it’s fairly priced otherwise. He could of course opt to use aftermarket parts and finish the job with change left over.

Horses for courses and all that

 

[ChrisHGTV]

ah I’m with you, I thought you were suggesting you could get everything done for a grand. When I bought mine i mentally budgeted for a grand or so (couple of bags not incl fitting) as like you say the components are basically service items and seem to last 5-10 years. Luckily one airbag on mine failed within a week so that got done under warranty. So I’ve spent £1500 on the rest with a mix of genuine and aftermarket parts (Arnott bag and valve block, the lines and compressor being Merc). So £2k all in using an Indy and me supplying some parts From Autodoc. The compressor I could have done quite a bit cheaper (it was about £700 fitted) but to be honest I just wanted it sorted quickly and wasn’t bothered about the cost. Like you say as long as you appreciate some expense is likely... What caught me out was the unexpected compressor needing to be replaced and there’s quite a few little add ons that add up, like the calibration, and even the brass air line joiner which is like £40. Hopefully now mine is basically all new it should be good for a few years, once I get the latest sensor issue sorted! Still a lot of car for the money, but I would be annoyed if I’d not already factored in some of the cost When I bought it.

 

[Will]

To be fair, there’s plenty of these out there being used daily with slow leaks and some are none the wiser (especially if no faults come up on star either)

I think the OP is lucky that the seller has been quite honest about this car.

I had a similar issue on my old 2011 S212 (an E63) which would drop if left for a few days - only slightly, but I knew it shouldn’t.

Had both airbags replaced under warranty, along with fitting - which was fortunate.

That’s all my one needed. OP could be lucky, or on the other hand could need further work like in your case. But then that could happen to any of these cars

 

[ChrisHGTV]

To be fair, there’s plenty of these out there being used daily with slow leaks and some are none the wiser (especially if no faults come up on star either)

I think the OP is lucky that the seller has been quite honest about this car.

I had a similar issue on my old 2011 S212 (an E63) which would drop if left for a few days - only slightly, but I knew it shouldn’t.

Had both airbags replaced under warranty, along with fitting - which was fortunate.

That’s all my one needed. OP could be lucky, or on the other hand could need further work like in your case. But then that could happen to any of these cars

Yes to be honest mine only had a very slow leak and I could have probably left it but I’m a bit of a perfectionist with my cars! Plus it’s nice to have that peace of mind, we often (before lockdown at least) do a few European trips a year with the bikes. The S212 is such a good tool for that. We did a single run Guildford to Dordogne and it was effortless.

 

[Will]

Yes to be honest mine only had a very slow leak and I could have probably left it but I’m a bit of a perfectionist with my cars! Plus it’s nice to have that peace of mind, we often (before lockdown at least) do a few European trips a year with the bikes. The S212 is such a good tool for that. We did a single run Guildford to Dordogne and it was effortless.

If you’re keeping it, it’s a no brainier to get sorted out. One of those jobs that will need doing at some point anyway, and the longer you leave it the more chance of further damage - eg compressor etc. A stitch in time and all that

 

[edgersoldchap]

The self-levelling suspension can be a bit of a pain when it comes to identifying exactly what is wrong with it. My S211 would frequently go down completely overnight on the passenger side and occasionally on both sides. It always pumped up within a minute of starting the engine in the morning and worked normally when it was being driven, My indy had many attempts to resolve it but without success over a period of about 5 years. He couldn't find any leaks in the bags, changed the control unit and compressor, checked sensors etc. all to no avail. it got to the point where I was considering converting the rear suspension to a standard spring set up using a conversion kit that's available but it would cost around £1200. Then I had a problem with a missing reluctor ring so decided to change the car as it was all going to cost too much with a service and MOT also due this month. I now have an S213 (which also has self- levelling suspension!).

I think I was unlucky with the S211 - I had it for 13 years and it was otherwise a great car. Personally, with the experience I have had, I wouldn't buy the car unless it was fixed first. However honest the seller appears to be about it, you do not know exactly what the fault is or what the remedy will be - knocking something off the price might not be an adequate solution. I would have thought he would have had it fixed before putting the car up for sale if it was just a simple change of airbag, compressor or whatever.

Marco

 

[ChrisHGTV]

The self-levelling suspension can be a bit of a pain when it comes to identifying exactly what is wrong with it. My S211 would frequently go down completely overnight on the passenger side and occasionally on both sides. It always pumped up within a minute of starting the engine in the morning and worked normally when it was being driven, My indy had many attempts to resolve it but without success over a period of about 5 years. He couldn't find any leaks in the bags, changed the control unit and compressor, checked sensors etc. all to no avail. it got to the point where I was considering converting the rear suspension to a standard spring set up using a conversion kit that's available but it would cost around £1200. Then I had a problem with a missing reluctor ring so decided to change the car as it was all going to cost too much with a service and MOT also due this month. I now have an S213 (which also has self- levelling suspension!).

I think I was unlucky with the S211 - I had it for 13 years and it was otherwise a great car. Personally, with the experience I have had, I wouldn't buy the car unless it was fixed first. However honest the seller appears to be about it, you do not know exactly what the fault is or what the remedy will be - knocking something off the price might not be an adequate solution. I would have thought he would have had it fixed before putting the car up for sale if it was just a simple change of airbag, compressor or whatever.

Marco

If the OP can get a good price for it, and factors in/budgets for worst case scenario £2k to renew most of the system it could still make sense. As Will says I think you have to treat the whole system as a consumable then you won’t be disappointed! In my case it’s been the frustration and 5 attempts by the Indy to sort it rather than the cost tbh, but it still works out £200/year for maintaining the self levelling. In hindsight I would have probably instructed the garage to replace everything bar the compressor at the first sign of any leak. My compressor body leaking I think is quite rare, and if I had had the time (and if the car wasn’t stuck at the garage) I would have rebuilt it myself or fitted a cheaper aftermarket one. From what I can see on the forums the life expectancy of the system seems to be 10 years give or take.

 

[ChrisHGTV]

I was going to add, if you look at a car of that age that isn’t leaking and it hasn’t had stuff replaced yet you know that you’re still likely to see some expense at some point down the line!

 

[milleplod]

Well, I bought the car, and I got it with a very good price reduction indeed! The rear end actually only sinks on the nearside, overnight. I'm thinking I might as well replace the airbags irrespective of where the leak might be, as the car's 10 years old now.

I've Googled, and seen lots of advice and recommendations that steer me towards Arnott parts. However, I've also found Dunlop-branded ones that come with a 2-year, 20k miles guarantee. Any thoughts on these at all? My mate's mega-expensive camper (sorry....luxury motorhome!) has Dunlop self-levelling units fitted he tells me. The 212 ones are £200 a side.

Pete