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Sorry I cannot answer any of your questions! I ordered and have the special tool for the ABC fluid change out as I plan on keeping my ‘19 SL550 indefinitely but still cannot find out how the filter comes out the top of the reservoir. Obviously the wire bail wire unclips from the cap but at that point no amount of pulling on the thin “ears” on the cap results in it coming loose with the filter attached. I have tried twice to remove the cap and filter but am afraid I will break the cap. If you figure it out please write back in to help the rest of us. A call to my local dealer gave no results. They say they have never done it and the fluid is permanent. LOL In my opinion when the fluid starts to loose its light green color out it goes!😊
The cap pulls up but you need some force to do
it. The cap had two o-rings on it in my case so a bit stiff. Gentle consistent pressure and some wiggling and it will come out.
Originally Posted by Utopia Texas
Sorry I cannot answer any of your questions! I ordered and have the special tool for the ABC fluid change out as I plan on keeping my ‘19 SL550 indefinitely but still cannot find out how the filter comes out the top of the reservoir. Obviously the wire bail wire unclips from the cap but at that point no amount of pulling on the thin “ears” on the cap results in it coming loose with the filter attached. I have tried twice to remove the cap and filter but am afraid I will break the cap. If you figure it out please write back in to help the rest of us. A call to my local dealer gave no results. They say they have never done it and the fluid is permanent. LOL In my opinion when the fluid starts to loose its light green color out it goes!😊
I'm pasting here from my post of 10/16/21 under title R231 Intermittent sound from ABC pump or damper:
Posted 10/16/2021
OK here is my 2 cents Re the ABC system:
I'm a former Submarine Nuclear Power Plant Engineer so well familiar with mechanical systems and hydraulics for sure.
Let me start by saying I am now on the 2'nd SL550 with ABC (1'st was a 2015 and now a 2018); love the car, love the performance of the ABC so much that I bought out the lease on the 2018 and plan to keep it like the 1986 560SL with 32K original miles that sits beside the SL550).
"0" issues with the 2015 that I had for 3 yrs and 30K some miles.
Had "minor" leak from R rear strut on the 2018 1 yr in @ 5K mi. I believe the leak was caused by running over an abrupt 2" step in road bed under construction (paving crew did not provide a taper between milled roadbed and the new top coat) that obviously introduced a rapid hydraulic shock to the system that in my opinion weeded out a weak component (the strut that developed the minor leak). Leaking strut was replaced under warrantee complete system check including rodeo performed and all other components shown to be OK......so....in my opinion this was a good test of the system and the R rear strut that was an "infant mortality" was wedded out. Maybe my failure was similar to the one other strut replacement I know of...if so understandable and again weeds out infant mortalities.
Sure would like to hear from MB as to their suggestions for ABC maintenance but, no where to be found so we on our own.
Back to the ABC and R231s:
As Wolfman has said the R231 ABC system is greatly improved over the R230; here are just a few of the improvements:
1) Hoses moved from areas of hi heat (moved from under the engine that also required engine removal for replacement). 2) Hoses, valve block & accumulators location and assembly redesigned for ease of replacement of components (assembly tilts down for component replacement w/o need to remove lines so less expensive labor vs R230).. 3) Valve block valve seals using better material. 4) Struts redesigned (this reason for not yet being able to purchase rebuilt units as not enough failed units available for rebuild). 5) ABC filter media redesigned to filter out smaller particulates 6) Fluid canister redesign to preclude owner and dealer/service contamination. 7) Pump pulsation damper relocated to immediate pump discharge to smooth out high pump discharge pressure and respond to system surges vs letting the pump see high system surges (increases pump reliability) BUT....by placing the pulsation damper on top of the engine and subjecting it to high ambient heat the life of the rubber diaphragm in the damper (accumulator) is affected causing I believe need to look at the pump pulsation damper as a maintenance part that should be replaced as a PM. My belief seems supported by the few reports of need for pulsation damper replacements we have seen. Based on this I plan to replace mine as soon as I feel vibrations or maybe @ 50K miles or 7 yrs as a precaution to insure it is operating as designed. 8) Important to watch fluid color and fluid level as both are tell tales to proper system operation and longevity: a)Insure you know how to check fluid level as it will tell you a lot . MAKE SURE you clean the area around the dip stick before checking so you are sure contaminates are not being introduced into the canister ! Fluid level is different with engine running vs when engine off.....with engine running level on the dip stick is the lower mark..... lower than when engines is shut down as the system is pressurized when running and the 3 accumulators (F, R and Return) are pressurized with pump providing pressurized fluid compressing the diaphragms in the accumulators against the nitrogen charge thereby providing the give and take needed as the struts rise and fall...BUT when the engine is shut down the nitrogen in the accumulators displaces the fluid back to the ABC canister raising the level. b) If fluid level was OK but now down it means you have a leak somewhere (easily visible by under car view) but, if no leak then LIKELY is sign of an accumulator diaphragm leaking internally AND putting strain on the system by not moving sufficiently to allow design give and take that will lead to failed seals in the struts or leaking/blown supply lines and or stressed/failed pump
SO.......Really important to do the following: 1)Check periodically or have the MB dealer check ea service for fluid level AND color of the fluid Fluid level falling requiring adding fluid but no signs of leaks under the car indicates likely accumulator internal diaphragm leak and as the accumulator not operating as designed will put stress on all ABC components. Fluid color is a sign of deterioration of rubber in the hoses or accumulators diaphragms (it's the rubber deterioration that turns the color from clear green to dark green or blackish) and I believe as long as fluid level is constant (no need to add) that just a fluid and filter change is all needed.
Bottom line:
If I have no fluid drop but, color change I will change fluid and filter.
BUT
If I see fluid drop and no under car leaks I will suspect an accumulator failing and probably change all accumulatos.
Notwithstanding the above I will swap out the pump pulsation damper at 50K miles as cheap insurance.
Also understandable that over time the accumulators will need replacement (the rubber diaphragms will leak internally and lack of proper accumulator function will put strain/shock on all ABC component accelerating potential for leaks/failures) so monitoring fluid level is important.....insure your dealer tells you if need to add fluid as it is sign of accumulator failure.
FYI:....If when the dip stick is pulled and if there is a rush of air could mean that one of the accumulator diaphragm has failed and the nitrogen charge in the accumulator has expelled into the system and into the ABC tank so when pulling the sealed dip stick the nitrogen is expelled.....just another thing to look for.
Bottom line: The system is well designed, operates very well and performance of the car with it is so much better than without BUT, like anything complex it will need observation and maintenance (better yet preventative maintenance that will be less expensive that waiting until failures. As I have said the system on our R231s has been improved such that the preventative maintenance of fluid/filter, pump pulsation damper and when needed the 3 accumulators will be much less expensive than was the case with R230s
NEW:
In addition I agree with what Sebastian has said above about the cap removal (my dealer who has worked on 2 R2131 ABC systems said the same thing (BTW...my dealers Hd Tech told me the failures they have seen relate to impact with LARGE pot holes....Im one case the Pulsation Damper blew apart, in the other strut leak caused by pot hole impact.
Overall after recent discussion with the MB Hd Tech he agrees that my suggestions above regarding fluid change and PM for the Pulsation Damper and Strut Accumulators is good insurance.
I have 7 yr/75K mi total coverage on my 2018 (purchased Extended Factory Warranty that covers the accumulators and struts....note the CPO does NOT cover ABC struts but, the EFW does).....My dealer said they would check before coverage expires and if any indication of Damper or Accumulator failure looks likely will take care of (nice). In meantime I plan on at my expense replacing the fluid and filter if color changes, having MB replace Damper or Accumulators if fluid level drops.
BTW: the fluid tool discussed above will work once the cover is removed.
ABC fluid flush performed at 20.9k miles in March 2022.
Done at Mercedes dealer by a very conscientious and capable shop foreman. Dealer charged 4 hours labor.
About 11.5 liters of fluid was exchanged to achieve clean fluid. I had provided 21 liters which were on hand at the time of service, but the balance was deemed unnecessary.
Parts required:
- Pentosin CHF 11S (MB approval 345.0) — my source was FCP Euro online
*Or* MB part 001989240313 (incredibly overpriced)
- “Oil tank” which is the ABC fluid reservoir with integrated filter (filter cannot be purchased separately) — MB part # 231320001428
Pictures description:
Left: fluid at operating temperature 20.8k miles. Appears to show medium wear.
Middle: virgin fluid
Right: fluid after the job. As you can see, it’s not completely virgin
I wanted this ABC fluid exchange carefully documented. The following appears on my service paperwork:
<<
Per customer request perform ABC suspension system hydraulic fluid exchange procedure with “rodeo mode” preparation and ABC filter assembly replacement. Exchange fluid using customer-supplied 345.0 MB-approved Pentosin CHF 11S fluid. Install new MB filter assembly MB part #231-320-00-14-28 purchased by customer at MB Fort Pierce parts dept. Color of Pentosin fluid verified identical to color of MB brand fluid. Customer has provided sample of system fluid extracted at operating temperature at 20,872 miles as well as sample of new Pentosin fluid for comparison. Sample fluid noted as adequate to good quality showing medium darkness wear and tear. After fluid exchange procedure complete rodeo mode cycle again and extract system fluid sample for comparison with previous two samples. ABC system fluid verified clean after about 11.5 liters exchanged. System fluid level is correct. Road test vehicle and reinspect for leaks. No leaks or errors found. System operates normally.
>>
******
Some notes about prices:
Be sure to search Mercedes-Benz part numbers online and find the cheapest prices sold at competitive online Mercedes dealers and negotiate with your local dealer as necessary at the parts desk. There’s no reason to pay more than another Mercedes Dealer is charging. Clever dealers are attempting to charge over list price for parts which is crazy. Competitive online dealers continue to sell below list. The Hydraulic fluid is a fraction of the price from FCP Euro. Would you rather pay $16 from FCP, Mercedes list price at $41, or Mercedes’ “market” markup price of $71 per liter! If the local dealer has a problem with you supplying the Pentosin fluid, tell the parties involved you don’t intend to spend hundreds of percents more than you need to on fluid — especially not at 10-20 liters. At worst, show them the price for which you can obtain the fluid and offer them a 30% markup over the price you can pay on your own. The Pentosin fluid shows the 345.0 MB approval and it’s identical to the Mercedes-Benz brand fluid — so there’s no backdoor excuse “We cannot guarantee non-genuine parts.” Pentosin is the same fluid used in the Mercedes-branded bottle.
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Again, I would like to give BIG THANKS to Herman K, fellow forum member. Thanks Herman and all those who have helped simplify the ABC maintenance procedure!
I have changed my ABC fluid and filter on my CL600 at 30,000 miles at the Mercedes dealership for $360, everything ( fluid, filter, rodeo) included. I have asked them to show me the old filter, the fluid was kind of dark, well darker than the new one, so I guess at least around the mileage that needs to be done....
Haha
Steve, if you're talking about me, my comments have the same warranty as anything you find on the internet, so there's always that.
Honestly, this thread is made up of extremely savvy folks with lots of participation. Looking at the comments, including yours, I can see nothing constructive I can add at this point that many of the fine people haven't already covered here. Plus, I have learned to swear at every flavor of ADS, ADSII, ABC, Magic Body Control, etc... possible since the hydropneumatics of the Citroen DS. So I get a slight twitch of the right eye when I read these threads mentioning Pentosin or hydraulic fluid.
btw. I do agree with the general consensus that the R231 is improved over previous iterations, but it's been a long hard road
I'll see if there's anything I can add to the posts you mention though, and I can PM you. You can always edit your posts for future reference.
Cheers!
Last edited by crconsulting; 03-28-2022 at 06:20 PM.
I ended up ordering o rings from McMaster carr in the proper materials. Basically i did not have the time to spend at the parts counter so i measured up the od- id and thickness.
Filter part number is on the thread above. I will post a list when i dig it up for the people who wants to go this route.
As for the car it is performing flawlessly no suspension noises or leaks. I did have to do a small top off but very little. The less you have to poke around in there the better it is.
The car did get the front sway bar links changed as we could hear that knock sound.
- “Oil tank” which is the ABC fluid reservoir with integrated filter (filter cannot be purchased separately) — MB part # 231320001428
On my EPC, I show filter as part number 231320006928 no? maybe I missed it in this thread, did someone try to order this and it wasn’t available separately? Or no availability? (Edit: just looked, nope, what a pain 🙁 sorry fellas )
Last edited by crconsulting; 03-29-2022 at 12:51 AM.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by tx170754
I have changed my ABC fluid and filter on my CL600 at 30,000 miles at the Mercedes dealership for $360, everything ( fluid, filter, rodeo) included. I have asked them to show me the old filter, the fluid was kind of dark, well darker than the new one, so I guess at least around the mileage that needs to be done....
That's a bargain! I thought they charged $360 just to drive the car into the service bay. At that price, I'd have it done every 10,000-15,000 miles. Having performed an ABC fluid change myself on my R230 SL500, I would gladly pay that to have it done professionally.
That's a bargain! I thought they charged $360 just to drive the car into the service bay. At that price, I'd have it done every 10,000-15,000 miles. Having performed an ABC fluid change myself on my R230 SL500, I would gladly pay that to have it done professionally.
Yes, it wasn't expensive and they do a great job, I service both my Cl and SL to that dealer, no complains !
I live between two Mercedes dealers ( almost the same distance ) one bad and one good, believe it or not !
I have changed my ABC fluid and filter on my CL600 at 30,000 miles at the Mercedes dealership for $360, everything ( fluid, filter, rodeo) included. I have asked them to show me the old filter, the fluid was kind of dark, well darker than the new one, so I guess at least around the mileage that needs to be done....
I take you at your word, but I have some questions about how this procedure could possibly be done at $360.
The hydraulic fluid at Mercedes costs $41 at list price and $31 at discount price. Even at FCP Euro’s rate at about $18/liter, I don’t how this can be done at $360 by simple math. You’ll need to exchange a minimum of 10 quarts with 15-20 being preferred. This takes “a few hours” of labor at any dealer. My dealer charged 4 hours; and as you can see from my test tube sample, 12 liters didn’t quite do the job — I would say the fluid was cleaned to a level of about 85% of perfection.
Do you happen to have test tube samples that show that the fluid was exchanged clean? I’m not being wise — I’m just hoping the mechanic at this dealer actually knows how to perform this procedure.
I was there when they did it, i've seen the fluid before and after ( including the filter, as mentioned ) and also the "rodeo" procedure, I do not know what to say besides that.....My ABC fluid looks very clean to me now....Remember that was done on my CL 600 and not on the SL.
Update
My Sl 63 is operating like a beauty. No issues. I will start to do some more invasive preventative maintenance such as replacing cam sensors, cam magnets and the oil filter housing gaskets / associated o rings. I can see that the filter housing is starting to sweat a little so it needs to be dealt with . I will do turbo coolant line replacement as they for sure will break once I remove them. I just did this on my C207 with a M278 engine. now it is all tight again.
just enjoying the Cali winter with mild convertible weather.....
Thanks for all the good info and insight.
I have a 2013 SL550 (R231) with around 17K miles on it. ABC fluid still looks somewhat clear and green however after 11 years the filter needs at least an inspection. However with clip removed I have not been able to get the filter assembly loose. The only thing I can "grab" is the tab on top that has a hole in it. Previous posts state that they were able to "wiggle" it loose. I have tried but I'm afraid of breaking the tab off. Short of using a hand grenade or crowbar I called a timeout before I brake something.
I was thinking of removing the screws that secure the top of the reservoir and pull the filter assembly out while still attached to the cover. With engine not running there is no pressure ....
A question for those that have gotten the fiter out : Can this be done WITHOUT making a mess and me taking a hydraulic fluid bath?
Thanks in advance.
Thanks for all the good info and insight.
I have a 2013 SL550 (R231) with around 17K miles on it. ABC fluid still looks somewhat clear and green however after 11 years the filter needs at least an inspection. However with clip removed I have not been able to get the filter assembly loose. The only thing I can "grab" is the tab on top that has a hole in it. Previous posts state that they were able to "wiggle" it loose. I have tried but I'm afraid of breaking the tab off. Short of using a hand grenade or crowbar I called a timeout before I brake something.
I was thinking of removing the screws that secure the top of the reservoir and pull the filter assembly out while still attached to the cover. With engine not running there is no pressure ....
A question for those that have gotten the fiter out : Can this be done WITHOUT making a mess and me taking a hydraulic fluid bath?
Thanks in advance.
This is likely not helpful but the filter on my R231 SL is integrated into the reservoir as one piece; not sure if this is the case with R230.2.
Thanks for all the good info and insight.
I have a 2013 SL550 (R231) with around 17K miles on it. ABC fluid still looks somewhat clear and green however after 11 years the filter needs at least an inspection. However with clip removed I have not been able to get the filter assembly loose. The only thing I can "grab" is the tab on top that has a hole in it. Previous posts state that they were able to "wiggle" it loose. I have tried but I'm afraid of breaking the tab off. Short of using a hand grenade or crowbar I called a timeout before I brake something.
I was thinking of removing the screws that secure the top of the reservoir and pull the filter assembly out while still attached to the cover. With engine not running there is no pressure ....
A question for those that have gotten the fiter out : Can this be done WITHOUT making a mess and me taking a hydraulic fluid bath?
Thanks in advance.
I would not mess with it, my SL500 is gone but the dealer did it for me, it wasn't expensive....
03-06-2022, 01:14 PM
