ML270 W163 2002 Brake fluid leaking under dash

[benzdriver737]

Was wondering if anyone else has had this problem. I think it's brake fluid leaking from somewhere above, but I can't (as yet) find the source.
Brake fluid level seems ok in the reservoir.
Could it be something to do with the air conditioner.?
Any advice...
I may have to remove the dash front to find the source.
How hard is it to remove the front of the dash.... looks like it comes off as one big section.
Anyone had experience removing the dash front.?

 

[momomo]

I know you dont know the source but where is it gathering or where are you findding the fluid inside the car?

 

[ringway]

I know you dont know the source but where is it gathering or where are you findding the fluid inside the car?

momomo,

Here is the original thread with a picture
http://www.mbclub.co.uk/forums/showthread.php?t=64615

 

[momomo]

Thanks ringway , I must have missed that thread!

 

[benzdriver737]

Yesterday I removed the 'D' shaped panels either side of the steering wheel and managed to gain access to the area above the foot operated park brake.
I found a 'black box' (A030 545 26 32) wet with brake fluid, and the two plugs that attach to the 'black box' were wet with brake fluid.
I removed the neg terminal of the battery, then unplugged the 'black box' and used electrical spray cleaner to remove all the fluid as best I could.
I still can't see where it's coming from or how it managed to be there.
I think it may have something to do with the brake booster as it's roughly situated behind that area. Reconnected everything, put all the bits back in place, and all seems to run Ok.
I think I might let my local mechanic take it from here... brakes are something I don't wish to take lightly. (although they seem to be working ok)
Will post more info when I know what the problem is...

 

[momomo]

Are you sure youre not loosing brake fluid? If you suspect brake fluid, sometimes the seals inside the master cylinder can go letting fluid leak back into the brake booster. The fluid will gather in the booster and will eventually leak through pass a rubber seal where it fits inside the car.

 

[benzdriver737]

It's transmission fluid

Climbed under the car and found the transmission wiring plug wet with fluid.
Took the car to my local mechanic and he confirmed the fluid inside the car was transmission fluid.
Transmission fluid migrating up the wires towards the TCU (transmission control unit.)
The transmission electrical plug had previously been replaced in 2007, so I thought this problem had been fixed. (since found out that the transmission electric plug has been superseded two more times since I had the job done.... beware 722.6 owners.
Found a local supplier of Fuchs oil products, and so I have ordered ten litres of Fuchs Titan ATF 4000 and will have my mechanic change the fluid and filter while he's there replacing the plug.
Fuchs Titan ATF 4000 is about one fifth of the price of mercedes ATF yet it's the same product in a different bottle.

 

[benzdriver737]

wrong transmission fluid...

Was advised by MBDOC to use Fuchs 3353 and NOT 4000 with this transmission.
Advice appreciated and taken...

 

[stumo]

Hey benzdriver737, can you please pass on your source for the Fuchs fluid? I couldn't get it in anything less than a 205l drum here in Melbourne (Fuchs head office is here). And none of their local retailers I tried could get it in lower quantities from them either. So I was forced to buy bottles with the MB label on instead, and MB pricetag!

Oh, and yes, Fuchs 3353 IS the MB fluid (NOT 4000), Fuchs and Shell supply it to MB who put it in their own fancy bottles. Don't ever use anything else in these trannys.

 

[benzdriver737]

Fuchs 3353

My local supplier of Fuchs (country NSW) will supply 20 litre containers. (around $250)
If you wish to completely drain your transmission you will need to do a 'flush' which takes about 20 litres.
My local repair shop has a transfusion machine that completely drains the old fluid and replaces it with fresh fluid...
The Fuchs supplier in Albury also supplies 20 litre containers. (Fuchs 3353)

 

[stumo]

Thanks for the info, that is about half the price MB charges for the exact same fluid.

As for flushing... I wouldn't use a machine. I would instead use the pump inside the trans to do a flush. That way you are not exposing it to pressures/flow rates that it is not used to, and avoid possibly dislodging gunk. This dislodged gunk could then find its way into sensive areas of the trans, which is bad.

This is why many people say it is better to leave a poorly serviced trans alone, rather than give it its first oil change only after many years/miles of service.

The MB WIS has the procedures for doing a flush on these, using the transmission pump and diverting the flow from the fluid return line. It says it takes 13 litres to fully flush.

Your guys probably say 20 liters with a machine bacause they usually don't drop the pan first (and hence don't change the filter (only a $20 part)) so they get a lot of mixing of old and new fluid in the sump so it probably does a worse flush too.

I'd go wth the MB method... drop pan, replace filter, new fuid in pan, then flush 3l at a time diverted out at the return line. That way the only mixing of old and new fluid occurs in the torque converter, which you can't really do anyting about.

On my ML, I'm going one step lower, and am changing out a pan full (4 litres) at a time, and filters, over the course of about 10k km. That way it will gradually improve the fluid quality, and minimise the gunk dislogdge risk.

 

[benzdriver737]

Thanks Stumo... will take your advice and change 4 litres at a time

 

[stumo]

Can you please give me the name and/or number of the Fuchs supplier in Albury? Im going to be passing through there in a couple of weeks time and would like to get my hands on a 20l cube of 3353.

 

[benzdriver737]

Fuchs supplier in Albury

Bockman Batteries & Lubricants
551 Hume St.,
Albury NSW
Ph: 02 6021 3615
email: [email protected]