Checking 722.6 transmission fluid level - Page 2 - PeachParts Mercedes-Benz Forum

Ali Al-Chalabi · #16 08-27-2004, 06:27 PM

Gilly,

You are correct. My apologies as my eyes skipped over the word "many" when I read the post. Out of curiosity how many 722.6 fluid changes do you see done and is the fluid still clean and red after so many miles? I ask because the dealer where my car was purchased refused to the fluid change. I told them I wanted it done and they flat out told me no they won't do it. I didn't do it myself because I did not have a method to get the correct fluid level in there and din't want to get it wrong.

Gilly · #17 08-27-2004, 07:25 PM

Ali
Usually it does look quite dark, MB has already addressed this concern to the technicians, and will no doubt be a bone of contention for some time to come. In effect, what MB is saying is that "dark" or even "black" transmission fluid does NOT mean "dirty fluid". MB uses alot of graphite material in the clutch discs on this transmission, and it tends to turn the fluid dark quite quickly. Not "diesel oil change" quick, but quite fast. Initially the fluid was not tinted very red either, so the manufacturer was instructed to use more red dye in the fluid. So i am not surprised to see very "dark" (notice I said DARK, not dirty!) fluid in these transmissions even as low as 60 or 75000 miles. But MB points out that the darkness of the fluid is not a fault or an indication that the fluid needs to be changed. Maybei the "diesel oil" analogy is the best one. I mean, if a diesel engine owner went by appearance alone, they'd be changing oil every, what, 500 miles? And look how long those engines last, with that Black, Black oil.
Gilly
Gilly

blackmercedes · #18 08-27-2004, 08:03 PM

Well, I wonder what the "final" word is going to be on changing the fluid on the 722.6 trannies? Some people have had great success with their transmission even though they have never changed the fluid or filter.

I had a discussion with a Zone Service Rep some time back about this very issue, and he told me "if it were my car, I'd change the fluid every 100,000 kilometers or so."

Wouldn't life just be simpler if MB had just given SOME sort of interval?

jjrodger · #19 08-30-2004, 11:10 AM

Thanks Gilly. I'm going to leave it well alone and let the dealer check it out.

Ferdman · #20 08-30-2004, 01:23 PM

Gilly, out of curiosity why is the transmission fluid level checked at 80C? Is that an arbitrary temperature that the techs can achieve by simply driving a vehicle a quarter mile or so ... quick and easy, as opposed to full operating temperature?

Gilly · #21 08-30-2004, 06:12 PM

My take on that is that the dipstick tool is calibrated for that temp. It's also got a range for 25C I believe it is, not really sure why they don't say that it can be checked at 25C, maybe they just feel they are getting a truer reading at 80C. That's the best I can do, I do have some other info I can look through sometime also. There is a "range" on the stick it should fall into, I should point that out, and for anyone who can properly check the level, MB says to aim for the top of the range. Not over the top of the range, just maxed out.
Gilly

Gilly · #22 08-30-2004, 06:18 PM

PS I have a 722.6 Intro Manual up for auction at eBay, brand new in the wrapper, starting price $10, no reserve:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7919229168&ssPageName=STRK:MESE:IT

Gilly

jjrodger · #23 09-02-2004, 07:49 AM

I had the car in to the dealer today because I was really worried about it. The tech drove the car about 500yards, said this isn't the transmission, it's engine management, probably the MAA. He put it on the machine and apparently his diagnosis was confirmed. He showed me the print out but I can't remember what it said. The tech explained that when the air flow meter is defective, this can retard gearshifts and and generally confuse the car; the engine also felt down on power.

Sure enough, it runs like a dream again. Phew. Now, what can I do with that GBP5,000 I set aside for a new transmission...