SL55 R230 P30

[ThirdEye]

I've had 2 SL55s. My 1st was an '03 with all the issues that came with. Upgraded to a used '07 P30 with 72k miles, but the ride is killing me on the terrible NY roads here. The rear jumps laterally when going over bumps on a curve & is harsh on uneven pavement going straight. While the '03 drove like the tourer it was, the '07 feels too harsh to be intended for any a track that isn't perfect. For those who have owned an SL55 P30, is this normal?

The car is in great shape. Perhaps my bad getting a "track car" by buying P30? Can the car's response be reset softer using Star? If not, what about buying an ABC computer on eBay (they're cheap) & swapping it out (so I could swap it back for the next owner) or, are the rear struts different in a P30 that would I have to that new (used) box reprogrammed?

In general discussions about the ABC suspension, it is suggested replacing the accumulators. The car has never thrown any warning lights, never drooped, responds properly to the raise / lower button, etc. so I'm loath to spend thousands only to find that the car was within spec.

Open to all ideas from P30 owners or techs with P30 system knowledge, especially to anyone who's reprogrammed / swapped the ABC computer or softened the ride through STAR & can provide step by step instructions.

Thx.

 

[Teego]

I don't know the p30 but before major surgery I'd ask about oversized rims which will crash around bad roads. Also tyre pressure as over inflation gives a bad ride on anything less than a perfect surface.

 

[ThirdEye]

Agree with your Occam's razor approach. I maintain the pressure at the minimum recommended.

It is also true that the 19" rims mean low profile tyres, which is different by a bit from my '03. That said, I regularly blew out the front tyres on the '03 whereas I have yet to experience that with the '07 on the same roads.

My experience points more towards the system. I'm hoping someone with a P30 will comment on the ride when new(er) and the likelihood that it may be the ABC computer vs the accumulators vs something I haven't considered.

Thx & Best.

 

[ToeKnee]

When I had my r230 with ABC in sure there was a document somewhere on the net that have testing criteria for failed accumulators, pump etc. Sorry but I can't remember what site it was on but if you find it it may help you diagnose if there are any problems?

 

[ThirdEye]

When I had my r230 with ABC in sure there was a document somewhere on the net that have testing criteria for failed accumulators, pump etc. Sorry but I can't remember what site it was on but if you find it it may help you diagnose if there are any problems?

I'll search for it. Thx.

 

[Dickster]

My SL55 has new accumulators and rides quite harsh. I’ve always put it down to the 19” rims and low profile rubber.

 

[ThirdEye]

My SL55 has new accumulators and rides quite harsh. I’ve always put it down to the 19” rims and low profile rubber.

Do your 19" rims imply a P30 build? My non-P30 / non-F1 '03 had 18" wheels & was balanced over rough roads. What year is your car? Why did you replace the accumulators?

 

[ToeKnee]

Try here

https://www.abcspecialist.nl/uploads/documents/active_body_control_uk_2019_watermark.pdf

Or

ABC System

Welcome to my guide for the Mercedes Active Body Control (ABC) Suspension System. In July of 2014, I purchased a used 2003 Mercedes ...

mercedes-abc-drive-carefully.blogspot.com

 

[ThirdEye]

Try here

https://www.abcspecialist.nl/uploads/documents/active_body_control_uk_2019_watermark.pdf

Or

ABC System

Welcome to my guide for the Mercedes Active Body Control (ABC) Suspension System. In July of 2014, I purchased a used 2003 Mercedes ...

mercedes-abc-drive-carefully.blogspot.com

Thank you!

 

[Dickster]

Do your 19" rims imply a P30 build? My non-P30 / non-F1 '03 had 18" wheels & was balanced over rough roads. What year is your car? Why did you replace the accumulators?

No, mine just happens to have the split rims, no idea why or if it was factory. Mine is a 2003. The pulsation damper failed taking a hose with it. So I changed them all. They don’t last forever, so I would recommend changing them at around 40-50k miles.

I did a thread on the replacement process….

 

[ThirdEye]

After pursuing all the elusive, complex, technical avenues & being blunted at every turn I went for the direct: Deflate the tires. Before doing so I asked Michelin about their tolerances for the Pilot Super Sports. They referred me back to the sticker on the car - 35psi front / 36psi rear, which they (mis)quoted as 36 / 38. Using their misquote, I took the tires down to 90% inflation 32 / 34. Made all the difference: Still firm but no longer skipping over uneven pavement.

My research indicates that the Mercedes TPMS tolerance is 25% deflation before the light comes on. Can anyone confirm this? So far so good. I recognize that I'll suffer potential gas mileage & uneven wear penalties, but if one is worried about running costs, this isn't the right car anyway. There might be a slight handling penalty, but still handles better than all but a handful of cars, including the stock SL55. Hopefully the potential pothole blowout syndrome won't be any worse.

The dealer was very nice but clueless. They drove the car around local decent streets & declared it perfect. For those who are curious (and you need to check your own chassis / VIN #), the P30 uses different struts front & rear, controlled by the same ABC Module (programming differences not known, if any). If anyone knows how the module is programmed differently, please share.

For those who were generous with their information, thx for all your thoughts & input.

Be well.

 

[Dickster]

Interesting I might play with the pressures on mine..

 

[alabbasi]

Your accumulators are blown. I'm surprised you don't have the ABC light go off every time you hit a pot hole.

Keep it out of sport and replace the accumulators

 

[ThirdEye]

Thank you for your input. Do you own a P30?

Do the facts that the car never sags even after sitting for weeks, stays level, goes up & down equally at all wheels when the height + button is pushed each time & resets down on the third push and that no lights ever come on, not even a blink, suggest that it may just be the way the car is sprung? Add to this that deflating to tires has changed the ride dynamics to an acceptable level.

I have seen many suggestions that the accumulators are the culprit when a ride feels harsh, but only when one or more of the above symptoms accompany the complaint. An experienced mechanic suggested that it could also be the pulse dampeners. Likewise I have read of people who replaced the accumulators and found that nothing had changed, especially when they had no other symptoms.

The reflexive response to replace the accumulators on an ABC2 car may not always be correct. There being no way to test them short of removal, it is the last thing a person presented with a harsh ride with a P30 should do. In response to my enquiry, AMG, and another P30 owner both said that given my description the car was fine. It was a track-based car, not meant for rough pavement. Are you aware that it uses different struts?

I wish it was otherwise, but this beautiful, taught car was just not meant for the old roads of a crumbling infrastructure. I'm not sure where you live in Texas, but having lived in both Austin & Houston, I can tell you that those comparatively newer cities have roads that would do the car proud.

Best.