SL600 ADS query (not problem - I hope!)

[PHAB]

Hi everyone,

Have just taken the plunge and purchased a 1999 SL600 Sport....I am a sucker for punishment and the V12 lure was too strong for me! The history on the car was great, 2 owners only...always main dealer serviced and cherished etc. It is a wonderful machine, the engine is simply a masterpiece even compared with the very best and I think the looks are becoming increasingly classic. It is silver on black with the panoramic roof and all the toys the '600 came with.

It has a few minor niggles which I am working through slowly - replacement of bonnet pad, worn control arm balljoints (my current diagnosis for the low speak 'clunk' on uneven surfaces, especially when steering), a misbehaving o/s xenon that only illuminates when it feels like it...minor abberations to what is a magnificent car. Im aiming to gently restore it over time to make it as OEM and factory fresh as possible but first I want to make sure its mechanically sound.

I did a lot of research on the cars and the ADS (ADS II I believe on my car) is a cause for concern and this is where my current query relates to. The ADS appears to be working fine - the ride is supple and smooth in normal mode and significantly more taught in 'sport'. In addition the car also raises up and down correctly on demand (albeit pretty slowly and with a bit of creaking/noise). However I have noticed that the o/s rear corner sits 2-3cms lower in any mode than the other 3 corners (they all sit at 68cms from the ground and the o/s rear is more like 65.5cms) . Obviously this is not right. Having consulted the history on the car the previous owner spent £1700 500 miles ago having a new control valve fitted and the system bled and refilled at MB Bedford to cure a leak. Could it be that the system was not properly recalibrated / levelled afterwards which explains the slight dip on the o/s rear wheel? If there are any DIY diagnostics I can try before dropping it into MB myself to investigate (likely at huge cost) please do let me know....perhaps I should not be worrying about it?!

Any info would be really appreciated...ive scoured the forums and all the topics on ADS seem to be around the system not working / warning lights on....nothing with my particular problem. Thanks in advance! Will get some pics of the car up here once the sun comes out.

 

[BTB 500]

Yes your car has ADS II.

Is this with the engine running or at rest (or both)? Is it any different after you've raised and then re-lowered the suspension?

2-3 cms is a fair difference, mine sits approx. 12mm lower on the offside but I was told this was normal due to wear & tear on the springs and no cause for concern.

I can highly recommend SS Motors near Weybridge - they are ADS specialists. I use M-B main dealers for all routine work on my SL but got SS Motors to replace the ADS accumulators. As you're in Surrey I would suggest getting them to take a look if you're concerned.

 

[andy27168]

Hi,
SL600 lovely cars and quite rare in the 600 guise. Cant help with any DIY diagnosis that can be done, it will need to be plugged into STAR for diagnosis and then someone that is experienced in interpreting the fault codes it brings up.
These suspension systems can soon chew through your budget when chasing/rectifying faults, so I can only recommend to get yourself a good indy experienced in these cars/suspension system.
My advice would be to use Olly (forum member and sponsor BlackC55) at PCS in Horndean just down the A3(M), thoroughly recommended by forum members on here.
Mercedes Benz & Smart Specialists | Prestige Car Service | Horndean, Hampshire

 

[PHAB]

Yes your car has ADS II.

Is this with the engine running or at rest (or both)? Is it any different after you've raised and then re-lowered the suspension?

2-3 cms is a fair difference, mine sits approx. 12mm lower on the offside but I was told this was normal due to wear & tear on the springs and no cause for concern.

Hi guys, thanks for your suggestions.

This happens with or without the engine running, and when raised it maintains the same 2-3cm difference, ie it raises the same amount but because it started off being 2-3cms lower thats the way it remains. Should re-iterate...no warning lights, sport mode works fine, car rides beautifully, raises and lowers as it should....it just is lower on the n/s rear than the other 3 corners....

Might drop into SS or whizz down to Horden and see what they think when I have time...not causing any issues driving it but the concern is always there with ADS!

 

[BTB 500]

Incidentally, the ride height must be slightly out elsewhere ... it's not physically possible for one corner to be low and the other three to be at the same - correct - height (unless the car is bent!)?

Let us know how you get on.

 

[PHAB]

After a bl**dy careful remeasure its:

Front left and front right absolutely bang on 68cms

Rear left 67cms
Rear right 65cms.

Maybe I am being a bit too OCD about it. Ill stop in at Horndean or Weybridge and see what they think. Thanks for the pointers!