s5benzo

for my fellow ABC'ers or for general knowledge i found this article on the 215 section . really recommend reading the info on this site. this company is from germany and has done extensive reaserch and testing on the ABC suspension. along with their research are pictures that show the difference between maintained ABC and neglected.

http://www.exclusiv-automobile.de/ww..._Fahrwerk.html

use web page translator on google , its in german right now =)


they have a s55 with 430,000 km (266k miles) with all original abc components ... only replaced one hose and few dust covers. they changed the fluid every 30,000km (18.6k miles) . original pump still at 180+ bar............... PHENOMINAL IF YOU ASK ME .

mercy-me

Very very informative!! Thanks for sharing! A must read for all ABC suspension owners.

s5benzo

No problem mercy !! Amazing article

tusabes

A fluid and filter change costs what ? $700? If you do that every 18k miles, you've spent over $3500 on the abc system before 97000 miles.

s5benzo

Tusabes I know what your saying ! But there are a lot indy shops out there for a lot cheaper . I think if people sucked out a couple liters every oil change and replaced with fresh fluid that would help keep fluid new . Just a thought .... I do like the magnetic in line filter though , That definitely prolongs the life of the components.

s5benzo

I think if people serviced abc fluid every 30k would make a huge difference in reliability. Dirty and old fluid is the start of the problems

tusabes

Does anyone know how long the fresh fluid stays green ?

Does it change to light tan like the color of fresh motor oil almost immediately ? I checked the fluid on my cl500 and its light tan . If it were dark or burnt I would get it changed

Zax63

Does anyone speak German on this board? We should have them organize a group buy of the magnetic filter and post this, and the article, on the S,SL, and CL AMG and non-AMG sections of the forum!

kraut56

It basically says that Pentosin is hydroscopic, i.e. it will absorb water just like brake fluid. Therefore, fluid exchanges every 30 000 km ?20 000 miles are mandatory. The magnetic filter will trap microscopic steel shavings that the pump produces, and is therefore prolonging life of the ABC suspension components.
It points out that the ABC system has a design flaw, in that it only filters the return fluid, and not the pressure fluid.

They demonstrate that with the proper filtering system they designed the ABC and pump will easily last 200 000 to 300 000 miles.

Zax63

Yes, I used google translate and got all of this. Question is how do we all get our hands on "the proper filtering system they designed"? Group purchase?

jnash

I've emailed them to see how much the magnetic filter would cost and will post if they reply.
I guess though we could drop a magnet into the reservoir as long as it doesn't block the feed into the pump.

jnash

No, it changes slowly over time. They make an important note on their site that the oil in the struts does not come out when doing a flush. I assume that means doing a rodeo flush and filter run. So after a full flush you should do it again a few months later to get most of the diluted residual flush changed.
I did a full flush over a year ago and plan on another one as soon as the fluid arrives in the mail.

tusabes

Is your year old fluid still green ? Or light tan ?

jnash

Still green but it will be slightly darker than the fresher looking new fluid. Less clear and not so bright and fresh looking.

tusabes

Amazon .com has the cheapest pentosin if you buy the 20quart container for $210

jnash

oh man! thats a great deal! I just paid that much for 12 quarts shipped!

20 liters = 21 quarts!

speedracer58

I assume it's best to do the rodeo at the same time you are flushing the system? jnash I got my wife's car level by slightly bending the right rear bracket holding arm that goes to the level sensor. It didn't take much Maybe 3/8 of a bend up. It made the car level all the way around with in a 1/8 of a inch. I don't know if it got bent somehow or it has some other problem. Its been good for 4 days now.

jnash

Yes, that is how you flush the system. Suck out the old oil in the reservoir and refill. Discard the filter. Put the return line on the top of the reservoir into a bucket with a length of additional hose while doing the Rodeo until the new green fresh fluid shows up in the return line going into the bucket. Make sure you have plenty of opened ABC fluid ready to keep pouring the open top reservoir at the same time. It takes two people really. Do not allow the reservoir to be empty to allow air to be sucked into the ABC pump. Replace the filter after the flush.
Do another rodeo for 30 mins (15 mins each) and replace the filter again and top-up.
The final level when cold should be towards the lower mark or up to half way. Anymore and it will spill out later.
You may see leakage under the car during the rodeo. Mine did, It came out of the higher pressure discharge valve. Rodeo puts a heavy strain on the system and is a good test to make sure you your hydraulics are in good shape.

jnash

Rear ABC links can get bent for some reason. One of mine was bent and I straightened it in a vise, but later replaced all four with adjustable links.
1/8 inch all round variation is excellent! well done sir! It's not uncommon to have a variation up to 1/4 inch between driver and passenger sides even after you are done messing with it. Make sure your tires pressures are correct while measuring height.

fledda

Newbie here and sorry for this question. How and where do you check the ABC Oil so that I can see what color it is. Thanks

jnash

really?? This link will help you find the answer http://lmgtfy.com/?q=mercedes+ABC+fluid+check

fledda

Thanks, duh, I know Google is my friend.

kittyandgary

I used Google Translation, combined with my ancient knowledge of Deutsche (last time I really translated was in 1965 to pass requirements for technical doctorate) to bring the prose of this document to those who do not read/understand German. It's a bit long, and some duplication. (I made a couple of comments - in purple).
Gary--
---------------------------------------------------------------------------------
Mercedes Benz ABC Suspension
Our company has specialized on the ABC suspension for years.
We diagnose , repair, and replace all components in the ABC suspension.
For questions please contact our phone number. We are happy to help and assist you with tips and tricks that work.
What is the ABC suspension?
The ABC suspension is an electro-hydraulic active system combined with a coil spring.
The Active Body Control (ABC) can compensate within milliseconds to the rolling and pitching movements of the body when starting, braking and cornering. The ABC is thus superior to air suspension systems.
Care of the ABC system:
The ABC suspension has a gotten a bad reputation because many owners do not maintain it, and critical components become damaged – eventually destroying the whole system. Regular maintenance results in an ABC suspension with the same life expectancy of the rest of the vehicle. Below you will find some hints from our experience.
If it is operated for years with the original hydraulic fluid, or after this fluid has become dirty, then many if not all of the components of the ABC chassis can be destroyed. OR if it is operated with low fluid levels, the owner will have the same result. This includes the hydraulic pump, struts and valve units.
You can easily check your oil quality using the dipstick from the reservoir. This sits next to the fill cover which contains the white filter. Take a white lint free towel and pat the oil from the dipstick onto it. Clean oil is green, light brown in ‘fair condition. IT SHOULD BE REPLACED BEFORE IT BECOMES DARK BROWN OR BLACK. If it is very dark brown or black, replace it immediately (or be prepared to replace expensive components).
The system uses about 15-16 liter of Pentosinöl (A00198924003-10, or Pentosin CHF 11S). To replace you will need about 10-12 liters. This will replace MOST, but not ALL the hydraulic fluid, as some will remain in the individual spring reservoirs.
But, that is not a major problem. The large amount of new fluid mixes with the small amount of old fluid. You will also replace the filter in the ABC reservoir with the new 3mm filter. This new fine filter will clean the resulting fluid mixture. After about 750 -1500 miles you should once again flush/replace both the Pentosin fluid and the 3mm filter. Then you should end up with only clean/green fluid in the system. ( Anleitung_Spülen pdf. )
In one of the pictures you can see an additional filter, which we developed. This magnetic filter is specially designed to trap metal abrasion particles that can come from components of the ABC chassis. These metal shavings are caused when old ‘dirty/abrasive’ fluid flows through the ABC hydraulic pump, causing mild to severe erosion of metal. This magnetic filter removes any future metal abrasion or metal chips from the fluid, thus protecting the whole system (the fluid is repeatedly flushed and cleaned with every circulation through the reservoir).
Once metal shavings are created, they can infiltrate the entire system, making it necessary to disassemble the entire system and clean by hand!
The installation of the magnetic filter will help prevent this from happening. With the crystal clear case, as you open the hood, you can readily see and check the color of the ABC fluid and observe whether any metal has been collected by the filter. The filter is washable, so you make a one-time purchase. In the rare event that somehow something gets broken, all parts can be ordered individually.
CLEAN OIL is important for the long term durability of the ABC system
In the first picture you can clearly see an ABC pump that has run 120,00 miles in the clean ABC system looks like. In the pictures below, the pump has been running about 48,000 miles, and the fluid was very dark brown. The metal debris in the oil has produced fluid that is the equivalent of liquid sandpaper – which has rubbed and damaged everything - with every mile that was driven. Moreover, with this abrasive fluid, more friction occurs in the system, especially in the ABC pump. High friction means more heat. On some occasions pumps have become so hot that they overheat and glow! When this occurs, EVERYTHING DETERIORATES your fluid becomes progressively worse and begins to smell like burnt oil.
If the Pentosinöl in the ABC system is renewed every 15 to 30K miles, or every ~3 years, depending on load and driving style, the ABC system should last for 300,000 miles or longer.
This longevity has been proven by our own car and the maintenance we have done on it. This car is a W215 CL 65 AMG V12 Biturbo, and after about 6K to miles the fluid begins to turn brown. After 12K miles it is dark brown.
For vehicles with less engine power, it may take longer. But we have found the fluid usually starts to turn a dark brown to black color after ~18-25K miles. For vehicles that are have not had adequate service to the ABC system can change color even faster after the first flush/change.
We have driven our frequently used 2003 W220 S Class long version S55 AMG Kompressor ~250K miles. We have changed the ABC fluid approximately every 18K miles. All suspension components on this car are original except for 2 dust covers for rear shocks and a pressure hose to the right front strut. AND, the ABC pump from our vehicle had after all these miles is still ~190 Bar (~2,850 PSI) at operating temperature.
Our latest acquisition an S Class W220 S65 AMG V12 Biturbo long version 25K miles. The Pentosinöl was black as tar.
We had to disassemble everything clean and repair many components.
At this point, it is important - both for vehicle owners with ABC suspension (and Mercedes shop foremen and those who want to be) – to remember that the Pentosinöl has properties similar to brake fluid. They are both hygroscopic meaning they absorb water, such as from the air. Therefore, it is IMPORTANT that the Pentosinöl is replaced after a maximum of 5 years to prevent corrosion in the suspension components. (here they state this time interval is also recommended by Mercedes Benz – certainly it is for brake fluid, but not clearly stated for ABC fluid as far as I know).
For this reason alone, this fluid is not maintenance free as is always claimed by the MB dealer. You can check about the hygroscopic effect under brake fluid at Wikipedia.
Pentisol is hygroscopic, like brake fluid it absorbs moisture and deteriorates!
We found one incident where a SL 55 AMG was stored in October and brought out for driving in April. During the winter, the pistons had rusted in the ABC hydraulic pump. When first started, the pump was destroyed and there was, within seconds, a red error message on the instrument cluster.
"ABC defective please visit workshop". If that appears, the pump pressure is below 100 bar. At any pressure of 99 bar or lower, this red error message appears and the car DEFINITELY should not be driven further.
ABC pumps and systems are ONLY destroyed by bad fluid!!
The ABC pump is lubricated by the Pentosinöl and 200 bar pressure which it produces. This fluid passes through micro sieves and around and through very small passages to the main shaft and main bearings. Contaminated fluid first contacts the screens. These become partially plugged, and as a result the main bearings are inadequately or not at all lubricated. Then, the pump starts making bearing noise. When that occurs, if you then press the ABC button for lifting and your vehicle goes up.
During the raising of the vehicle the ABC pump is quiet for a short time. When it reaches full height, the pump becomes loud again!! Reason for this is that during the lifting operation, the main shaft is pressed under load into the main bearing, so the ABC pump for this moment is quiet. When the vehicle is at full height the load is no longer holding the main shaft to the bearing. Thus, the main shaft is rattling in the main bearings because the fluid pressure/film is missing.
IF the wear of the shaft and bearing is advanced, the pump is constantly loud.
It also happens that if the oil supply rapidly goes to zero, then the main shaft overheats the main bearing and they VERY RAPIDLY wear on each other. The pump is ruined. In these cases, repair is not possible. The pump housing is useless because the bearing seats are damaged in the pump housing and new bearing not available.
The most common cause of pump damage is the overheating of the pump through abrasive fluid. The metal debris in the oil is like sandpaper between the rotating parts. Due to the poor FLUID, higher friction results and the pump over-heats and is destroyed.
In rare cases, the pressure housing may crack, thus the pump leaks and fluid level drops dramatically. Also, the breaking off of the plugs from the pressure housing can cause this catastrophic loss of fluid and pump destruction.
Consequences of inadequate care and maintenance of your ABC system:
Dirty fluid will first slow the ABC hydraulic pump (plugged sieves). Many errors of the suspension result from the insufficient pump pressure. If the pump pressure of 200 Bar drops to about 160 Bar, the instrument panel will display in white/black: "ABC defective, please visit workshop".
If you then continue to drive the vehicle and the pump is working, the warning message will soon appear in red, (the pump pressure has dropped below 100 bar) and the ABC system goes into limp home mode. It closes the shut-off valves in the valve unit, so that the vehicle does not fall down. Your vehicle drives as if the shock absorber is defective.
With a red error message it is best to stop immediately and have your car transported to a service facility. If your ABC pump fails suddenly damage usually occurs throughout the system, as the fluid brings the chips with it. Continuing, the chips are distributed with the still small pressure in the system. That would be the worst thing that can happen. Your ABC suspension would then actually be a total loss. Mercedes Benz then recommends that all ABC suspension parts be replaced with new components. The ABC pump is a precision high pressure hydraulic pump that generates 200 bar, so everything must function precisely and with VERY low clearances. A metal chip left in the system is sufficient for the new ABC pump to be destroyed. Flushing the system in place brings no guarantee that it is clean, due to the branches (nooks and crannies??) throughout this complex system. A complete dis-assembly, flushing and cleaning by hand is the ONLY possible way to avoid future problems from such debris. Any other approach is Russian Roulette.
The cars we have serviced or repaired over the past years is proof of our approach. They continue to run well and do not return for ‘repairs’, only service.
Do you have questions, problems with your ABC suspension? Give us a call!
Phone : 03877-56 26 81 (Germany)

IF you are interested in seeing the components 'under repair', I strongly recommend going through the slide show of pictures at the bottom of their page.

Gary Knox
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A picture of the installed filter with 'good' Pentosin CHF 11S is attached. I'm also pursuing methods of making it available in the US.

fledda

I am interested in getting the filter as well. Please keep us posted. Thank you very much.

kittyandgary

Stay tuned, as I received a "yes, I'm interested in possibly pursuing this product" from my friend who has the aftermarket supply business for Porsche 928's (along with some other marques). IF he finds it worthwhile to move forward, I'll start collecting names of those who would commit to purchase (assuming $150-200 price here in the US).

Gary--