W211 e320 cdi transmission fluid

[dieselbenz1]

Well last year after checking through the records the transmission fluid had never been changed. So I changed 3.5 L and the filter. At the time the fluid was black. Over the last year I drained the pan and replaced 3 l twice but the color was still a deep coffee color. Today I changed filters again replaced 3.5 l of fluid the removed the trany return line at the radiator and pushed 3 l at a time 3 times by running the engine and refilling the transmission. The third time the fluid came back cherry red. So I'll monitor this and see how long that color lasts.

[engatwork]

That application may have a drain plug on the torque converter. There is a plug over a hole in the bell housing. Remove the plug and turn the engine over by hand. If it has a drain plug drain tc. too. To fill after draining tc put 4 qts in it, crank it up and add more until at correct fill line at correct temp.

[dieselbenz1]

Nope no torque converter drain plug.

[dieselbenz1]

I've left the belly pans off and found a slow transmission fluid leak. This is originating from the famous connector plug 203 540 02 53 so now that's on order as well.

[dieselbenz1]

I was dreading this job I did it 4 times before on different vechiles and only once did it go right.the 7 mm bolt must be stripped it won't back out. I turns with some force but doesn't back out. Broke the lock ring putting force while turning am nothing. Just looking for ideas here vice grips don't really work well.

[dieselbenz1]

Well I ended up punching around the base of the connector until it finally gave up. Chances are good I'll be needing a conductor plate now also. I did a brief check but welcome recommendations of a good brand name to be looking for.

[Zulfiqar]

For the conductor plate, genuine mbz is best (also sold at chrysler dealers)

Next would be kostal if you can find it.

But only use the round connector from mercedes benz dealership, it has thicker o rings with much better materials. I would also suggest to stop by a transmission repair shop and ask for a teaspoon of their assembly gel (its also sold as oreilly etc)

Slather the gel on the O rings and the casing and carefully align the adapter and send it home, it should seat smoothly, then tighten the bolt very gently,

[dieselbenz1]

Alright well before I saw this response I ordered one through a German auto parts supplier local they had on the shelf a Hudson brand?? Unit they claimed was popular so I purchased that. I actually had stopped in at a Mercedes dealership but the young kid told me just go out and buy an oring Mercedes doesn't supply those any longer. Ya prices vary foe those new conductor plates ranging from $39 to $1200 plus. I stopped at another dealer today and they can order the plates for $772 but I did pickup the connector from them it was on the shelf. Not that young kid gets under my skin oh well but I'm sure I'll get even. Everything went together smoothly and the tranny got another 5 + liters of fresh fluid sheesh. I got the advantage of practicing inserting the connector on the bench so that part was amazingly easy. Have yet to test drive it other than off the ramps and of course look for a leak in about a week. Maybe I should have just left that leak maybe lost 1 L a year.

[dieselbenz1]

Well it runs and drives just like before I wanted to fix that leak. Will wait a few days before seeing if it's still leaking.

[steve tampa]

DieselBenz1- from everything I've read, the reason to change the pilot bushing (p/n 203-540-02-53) is that originally, a bad o ring was used and fluid was wicked up into the computer requiring problems. The revised bushing is now used and for about $20, it's cheap. The 7mm screw holding it into the trans is captured and doesn't come out but pulling the bushing out after unscrewing it takes effort as the o ring is tight to prevent leaking and can be difficult to line up when installing. My 2005 now has 379xxx miles and shifts nicely. I clean the pan and use a new gasket and filter once a year when going on my summer 2 month vacation (about 8-10,000mi). Whenever I'm under the car now (up on race ramps or jack stands, I undo the drain plug and let it drain (3 1/2) quarts +- and refill. Seems to work and fluid is always clean. Cheap insurance. Steve

[dieselbenz1]

Nice to hear that. In my case the fluid was never changed 290,000 km. Last year I did the filter change fluid was black. This year I chased the leak to the connector o ring but the bolt that little 7mm refused to come out which caused me to replace the conductor plate. Next year I'll plan on dropping the fluid in the pan to see the color of the fluid. Thanks for the input!

[ah-kay]

Originally Posted by dieselbenz1

Nice to hear that. In my case the fluid was never changed 290,000 km. Last year I did the filter change fluid was black. This year I chased the leak to the connector o ring but the bolt that little 7mm refused to come out which caused me to replace the conductor plate. Next year I'll plan on dropping the fluid in the pan to see the color of the fluid. Thanks for the input!

Can't wait to see your result.

My CDI has 330k miles. I bought it at 260k. I replaced the conductor plate, changed fluid 3 times in the last 70k miles and the fluid is always black. It is caused by graphite inside the transmission, I believe. The car runs well so I never bothered but it would be interesting to see your result.