Been reading last few days about the infamous ABC problem on this model. Have a couple problems with my car lately (88K mile):

-vibration at 2.5 to 3K RPM
-beeping (ABC) when passing bumps.

Called my service provider and found out they replaced ABC pump last year under warranty And they replaced valve block at 60K mile couple years back

Diagnose result (cost $139):

-Vibration: just need new tranmission mount. (Easy and cheap)
-Beeping ABC: Need to ABC fluid flush and replace the spheres (4 total)
-Rear seal is leaking (big seal between tranny and motor) almost 10 hours job cost around $1600. I'm NOT gonna do this.

Problem is I never heard on this board that spheres need to be replace. So, I prolly will do the tranny mount and flush the ABC. Checked the ABC fluid and it was very dirty and a little low.

I will bring it to my brother shop and do the tranny mount cost $54 part. Should I give the dealer $600 to flush the ABC for me or I can suck the fluid out of the reservoir and refill it? My brother said I could do that.

 

Interesting to read of the ~2500 RPM vibration. I had exact same problem and replacing the transmission mount solved the problem. It's like night and day.

As for the ABC Flush, I read a different post about how someone pulled the fuse for the fuel pump so that the engine would turn, but not start so that he could flush a particular fluid. In this way, it may be possible to flush the ABC circuit more completely than just draining and refilling the ABC reservoir. In fairness, I have not tried this yet, but plan to in a week or so. Was going to work out the kinks and do a write-up, if successful. My ABC Fluid is rather dark, as well.

My plan is to drain the ABC reservoir, remove the return line and using extra tubing have the ABC circuit drain into an old container, then refill the reservoir. With someone in the car using the key to 'start' the engine, I would simply keep the ABC reservoir topped off until I see clear fluid exiting. I would finish by replacing the ABC Filter and put it back together.

In addition, I would hook up a spare battery (not battery charger) to help prevent the main battery from getting too low on voltage during this procedure.

Cheers,
Jeff

 

Good plan on the abc fluid. I'll see what my guy and me can do next week. Planning on suck it out and fill it up, drive around and do it again... Sounds like not a good idea since the fluid is so expensive at $25/ct. But my guy never touched this abc system before. I'll find out next week

 

That will ultimately cost you more as you will have change the filter each time before and after you drive. It will take about 10 quarts and 2 filters as you will change the filter before and after the flush. Unfortunately it is just an expensive procedure, damn abc, but there are not too many 4500lbs tanks that can handle like these cars.

 

Exactly! I think I used 11 liters of Pentocin and two filters.
Not a hard task really just make sure the level never gets low while flushing the system or game is over.
Johan

 

I think if you bypass the old filter during the drain you should only need one filter...do you agree? Why would you care about filtering the OLD fluid as you pull it...the filter is there on the return from the system.
I would say suck all of the old fluid you can from the reservoir and replace with new fluid, then pull the cap with filter out and discard the old filter, route the return line (without filter) into your waste container and keep the reservoir full while cranking the car...as a last step install the new filter with cap as you put the reservoir back and seal everything.
While doing thus flush, I would recommend raising and lowering the car multiple times with the buttons on the dashboard, that will give you a mini "rodeo" during the flush...keep us posted.
mike

 

As you described it here, that is the intent of my plan. I'm going to pour fresh ABC Fluid directly into the reservoir – with the ABC Reservoir assembly cap off/filter out – while the engine is cranking, letting the old oil (without a filter) collect in an old milk jug, or two, or three via the return line. Just not sure how many jugs I'll need. In my mind, I will need only one fresh filter when it's done. And yes, I could care less about filtering the old fluid.

However, your suggestion of the ‘rodeo effect’ is a good one. This raises a couple questions in my mind…
1) Legend and folklore has it that running the ABC dry, if even for a moment, is death to the ABC Pump, how does the factory initially charge or prime the ABC system? The entire system is bone-dry with barely-wetted seals during assembly, so how do they fill it the first time without burning out the ABC Pump? Anyone know?
2) What is the flow rate of the ABC Pump? One liter an hour is probably too little; one liter a second is probably too much. So how much fluid does the ABC Pump move per second, minute, month, year?
3) How many quarts does the ABC system hold?

Performing an ABC Flush using just the engine cranking may not allow the car to ‘rodeo’; that may require the engine running. Thus, the flow rate of the ABC circuit both statically AND dynamically (in motion) is critical to ensuring we can keep the ABC Reservoir full during the process. I'm continuing to research this project but it's next on my list for the S55; maybe a weekend or two away.

Cheers,
Jeff

 

I have read that you can Pressurize the pump prior to the initial start up...That is how the factory would do it. They fill the reservoir and thank put 10PSI pressure on the reservoir....with some sort of adapter.
I have read that 10 liters is sufficient for a flush, as far as the flow rate, good question...one way to find out is to pull the reservoir cap and lift the filter with the car running..nothing will run dry and you can view the flow...I would guess that a liter per minute might be average, under idle conditions.
One thing I am sure of, dont let the pump go dry...too much fluid in the reservoir during flush will be no issue, too little will be bad.
Mike

 

Good thoughts here, Mike. Thanks! Pressurizing the tank... hmmmm. Makes sense; similar to brake systems. Wonder if it's possible to make an adapter; gonna think about that one. Anyway, as I get stuff together and perform the task, I'll let you know how it turns out. Again, in a week or so. Thanks again for information.
Cheers,
Jeff

 

Ill look through my documents and see if I can score a picture of the adapter...I will post here if I can find it.

You sholdnt need to do that unless installing a new pump, I would venture a guess.

Mike

 

Yup! When I replaced my ABC pump some time ago I used a air gun in a cork like object and pushed in about 10/15 psi with the fluid already in there and it pushed the fluid flowing.
The flow rate is nothing like I had expected at all. It is actually really slow being it has so much pressure behind it. I would guess it was like 1 liter per minute.

 

Thanks for all the advices, ideas...I'll find out this weekend with my friend in his shop. Worst case scenerio, will pay couple hundred bucks for the MB shop or an Indy shop to do it.

 

I forgot to answer another question that you do in fact want the car running not cranking during this process. If you try just cranking the flush will kill the battery/starter for sure.

 

If someone have the pic of the return line (where we open, disconnect to get the fluid out) that would be perfect. I'm sure we can flush it ourself this weekend if I know exactly where to disconnect the return line!!!

 

The return line is the large connection at the top of the fluid reservoir, the filter attaches to the bottom of the return line.
Mike

 

Hahaha thank you! I think we can do it for sure. How many qt. of abc fluid required to do it? I'll buy at least 1 xtra qt. just in case.
Of course my friend know car stuffs but he never done this job before. Can we just do these steps:
-remove filter and point that return line to basket for dirty fluid
-Start the car and let it run while flushing the system (pour in the reservoir and make sure the reservoir dont get low). Raise the car up and down as well?
-keep doing until the clean fluid coming out and put the new filter in.

Is that simple???

 

I think that is all you need to do....you will need about 10 liters. I think you should take the car for a drive for 10-20 miles prior to starting the job, that will get the fluid heated up and circulating.
Mike

 

Thanks Mike, we definately can do it ourself. First I thought of we have to connect to MB computer system or s/t like that

 

Keep me posted on your outcome, I need to do this job on my 2005 car in the near future...My fluid is still clear green, but the car has 55K on it.
Mike

 

Done! The car run butter smooth now after changed tranny mount.
Did exactly those steps for abc fluid flush. Total 10 liters including power steering. I recommend you do the power steering while you are at it (eventhough my power steering fluid still clear). For power steering fluid, we used the oil extractor to suck out the fluid from the resevoir, fill it up, start engine and turn lefts and rights. Suck it out one more time and fill it up again). Also changed the ps filter as well. Let me drive a few days and see if I need to top it off or not. If not, Mike you can buy back 2 liters from me and save a few bucks

 

So can I flush the return line ABC fluid into a catch bucket while making sure the reservoir is topped up while also doing the rodeo with STAR?
Wouldn't that make the most sense to make sure you are flushing all of the lines even within the shocks themselves? Has anyone done this. I am not sure what the return pressure back to the resovoir while the engine is running. Is it safe or high pressure return?
I have STAR and filters, just need to go get 11 quarts of ABC fluid.
Would appreciate someone letting me know
Cheers
Jim

 

Exactly right Jim. The description is correct from when I did mine and the return pressure is not bad at all. Pretty slow actually I thought. Good luck
Johan

 

Yes, you can connect another hose to the return line and let it drains to the bucket. Like I said, since your already there. Suck the steering fluid out and change the steering fluid filter too. It took total 10 litters for mine.

 

great - thank you guys. I will go buy enough fluid