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Photo DIY: ABC Fluid Maintenance

173K views 72 replies 34 participants last post by  mrflex  
#1 ·
Granted, this procedure almost unworthy of a Photo DIY! But I think many (such as myself) left most underhood matters to the dealership technicians while the car was under factory warranty coverage. And given the expensive implications (pump damage, etc) if your ABC fluid level isn't maintained, this is probably something everyone should stay on top of.

Sample car is my 2005 CL500, chime in if there are significant differences in other years/models. We are at the right front of the engine compartment (driver's side for left-hand drive cars) as you stand at the bumper looking back toward the engine.

First, the location of the filler/dipstick plugs. (Indicated here by yellow arrows.) There are two and they merely pop off with a squeeze and a pull (they are not threaded). Although the power-steering and ABC systems are interconnected, their reservoirs are separate. The upper, larger one is ABC and the lower, smaller one is for power steering. The larger fittings with the teal-colored labels are the filters.

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Once removed, the dipsticks look like this (this is the p.s. one; the ABC one is longer). There are two markings... ***Edit thanks to our resident expert Eric: "Fluid should never be mid range, at the upper detent with engine off, lower detent with engine on." If mid range with engine on then there is too much fluid. See this note also.

Apparently you can remove them while the engine is running because my mechanic filled them through a clean funnel (highly advised) while the car was idling. And you thought this was a DIY ;)

However note 'official' instructions indicate that engine should be switched off!

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And now, the secret elixir: M-B Hydraulic Oil Q1 32 0001 (Pentosin CHF 11S; Product Code 1408107).

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Upon which it clearly states: Do NOT mix with other fluids. Insofar as a couple of members here have apparently experimented with admixtures of this and power-steering leak stop. I cannot in good conscience recommend such a strategy, particularly since those members were never heard from again! :eek:

This stuff costs about $37.50 per liter at your dealer (cheaper online of course). If your W215 has more than 25,000 miles, though, I'd consider the investment. You may never need it, but if you did, wouldn't you want some handy?

PS: See this post for a less-costly alternative Pentosin source. We still need some confirmation on any possible issues with respect to the alternates though. I expect it's the same thing.
 
#2 ·
Ace work Marsden! I'm going to check my dippers this weekend. Did the mechanic say anything about the fluid colour? There's a whole world of folklore about fluid colour(s) in Citroen hydraulic suspension land...
 
#4 ·
If you want to save some $$$$ Pentosin is avaliable at local euro part stores, it comes in a green can its like half price.... and please never put stop leak in the abc
i have witnessed first hand cars that people try to fix leaks with it and it leads to disaster usually pump failures or/including valves to
 
#7 · (Edited)
Very good post,
My ride is 2003m CL500, imported from Germany throw Japan, to the Saudi Arabia my car is not in normal suspensions control I don’t know what is the problems are there, the car is lifting up while stop and pressing the brake pedal once remove my foot from the pedal the car is comes down but when I drove it the level stay at normal position, I change fluid filter for the suspensions which hold part number as shown below.
 

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#10 · (Edited)
I changed my ABC filter and flushed the system. I would recommend it. I was a Auto tech for 18 years and you should see how bad the fluid gets. I think you should do that too both the ABC and the P S ( Power steering ) systems every 30,000 miles. The P S has a filter too. And don't forget your transmission Filter about every 50,000 miles. My oil was different, it came in the Blue MB can as above. Our MB Dealer did not have it in a bottle. GLTA
 
#15 ·
How do you change the ABC and PS (power steering) oil/filters then? Would you just suck it out and pour in the new oil? Are there drain plugs for either ABC and/or PS? How about the filter part numbers for both? Where are they located PLEASE?

I know there are lots of questions as I am a dummy as it come to DIYs (but I would love to learn). Thank you very much in advance folks.
 
#18 ·
flushes and filters

My indie (who retired from a MB dealership) told me it is critical to change the filters before you change/flush the ABC fluid. (I happened to stop by when he was working on a CL55 a local used car dealer - good reputation - brought in.)

After you do the flush, you change the filters AGAIN since they have collected the crap from the mileage/flush. Then you top off the ABC fluid.

Otherwise you will clog up the pumps and then you are in for BIG MONEY in parts cost.

According to him, the more you drive it the better it likes it as far as the ABC (and the car in general goes.)

I have had more experience with the ABC if someone has a question I will try to answer it or ask the retiree. I cannot respond in Internet time.
 
#20 · (Edited)
From what I am told...



I am referring to a flush of the entire system. Ivanj always takes a "systems engineering" approach, my friend.

(PM me for more experiences with ABC.)

You don't need to filter the waste oil per se since it will be recycled.

The existing filters are already compromised. The return oil goes through the new filters that catch the junk before they hit the pumps $$$$$ and valves.

Then you put in new filters for low $ and renew the oil $$$$.

The flush system you use maybe different - avoiding the new filters - but the MB techs were referring to the systems used by some MB dealers who made the investment.

The "retired" MB techs also said it is best to run the flush at the lower end of the pressures recommended. They said they have seen high pressure "quick and cheerful" flushes blow out the ABC valves and pumps - you don't want that $$$$.

After the service you might want to ask the dealer to put the ABC car through the "rodeo test." It is a necessary but not sufficient test to catch other problems (ABC pumps, for example.)

Hope this helps. Did I answer your question?
 
#23 ·
I am not commenting about the rodeo but the procedure for flushing the ABC seems contradict with what I have been told. When/if I actually do it, I shall see :).

I understood that the filter is connected to the return line; that way, stuff will be filtered before it gets back to the system again. When you flush the system, you would put the return line in the waste bucket/container, and add oil to the reservoir until the return hose come back with clean oil.

I will keep in mind both methods and see which one is right LOL
 
#24 · (Edited)
I found this over on another board from the UK.

Looks like it answers a few questions that have been asked in this thread.

I think one of the best things we can do as Mercedes Owners with ABC equipped cars
is to stay on top of our Tandem Hydraulic systems and make sure they are full and the CORRECT fluid and it is clean.

I bought a Green can of the Pentosin CHF11S over at the local Napa store for $ 20.00
You can use their online system to verufy the local store has it in stock too.

Love how my owners manuals for both my SL55 and CL500 never mention anything other than to "See your Dealer" when you look up ABC or Power Steering Fluid and checking it.
 

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#25 ·
The owners manual is useless. Despite the huge size, it is probably the only owners manual that I have ever seen that doesn't even show how to change the engine air filter, or even where to find it. Absolute garbage.
As for dealers, the markup vs. independent service (at least here in Calif.) is criminal. Plus, my recent experience with dealer service has been nothing short of pitiful. I recently had quotes from a local L.A. dealer for work in the $4k range.....had it done with original MB parts by an independent for about $1k.
Do it yourself and the savings are incredible....just take the time....most of this is not brain surgery.....and for those parts that require computer links, etc., find a good independent.
 
#26 ·
For whatever it is worth Bimmer Specialist OEM and original car Parts For BMW Mini cooper Porsche Mercedes Audi Volkswagen Saab Volvo| BimmerSpecialist.com sells the ABC CHF11S fluid for less than $20 per liter. Free ground shipping. Just click on Mercedes and than enter the Mercedes part no Q1 32 0001 in the part search window and it gives you two choices, one by Febi (an OEM automotive part maker), the other one by Pentosin. Febi does not make fluids, so they probably just repackage the Pentosin (the real manufacturer) brand in their own bottles. $13.99 for Febi and $19.89 for Pentosin.
 
#28 ·
I did call FEBI about their fluid and they sent me technical documentation so I could compare all the important parameters between Pentosin CHF 11S and the Febi fluid (Febi makes their own, I found out).
You may want to do the same with the Fuchs fluid. Get the technical data for both and compare. Viscosity at different temperatures, min and max temperature and foaming resistance are just a few. You also need to know if you can mix those two.
 
#29 ·
Hi,
I've got an SL500, 53 Reg...
I started getting the drive careful message so decided to top up the ABC oil.
I got the correct oil and then filled the reservoir.

I checked and topped up the oil with the engine running as everyone has said to do on here. I had it to the maximum mark.
I then turned off the engine, and the oil spurted out of the overflow holes on the dipstick everywhere. For some reason when I turn the engine off the reservoir fills up a lot more.

Are you supposed to check the oil with the engine running or not?
Should the engine be hot or cold?

Thanks
 
#73 ·
ABC Fluid level in reservoir

When car is on, lower part of dipstick...full
When car is off, upper part of dipstick...full
Best time to check, after drive for at least 30 min then leave the car running and check the dipstick mark, should be lower mark and not the upper.
Reason you had a spillage is that you top it off while car was running...too much oil in reservoir.
 
#32 ·
but then, after driving it would spread all over and leave marks that I could see without removing the cover no? I lifted the car with my mechanic and we did not see any sign of fluid this morning, nor on the ground after the rodeo test... is it normal that the level of fluid goes a little down within 8 month ?
Is it ok to wait and see while checking the level regularly?

Best regards.
 
#33 ·
The covers have contours and have places where the fluid can settle. Once the fluid hardens it becomes solid grit and will not flow out. It doesn't take that much time or effort to remove these plastic covers. If it takes 8 months for the fluid to leak just a little, then it is a minor problem now, but it may become a major problem later.
 
#36 · (Edited)
ok...and if those plastic covers are fluid free...any suggestion on the next step?... I have to add that my CL 500 stay parked for two month and that I read on another thread that it could result in some leaking of the fluid to preserve the system to over pressure...that could be another reason.... I will check the ABC fluid level and keep you guys posted on the results since the car will be moving regularly from now on...
and again thanks for your advices.
B. regards