TENNAc43

So this morning on the way to work my 98' c43 didnt want to shift out of second or third gear, hitting close to the redline around 40mph. It has done this before and always when it is cold. I will go out for lunch and the car will shift just fine. I have had the transmission serviced by the dealer less than 1k miles ago. Has anyone had a similar problem or knows of such behavior. Any preventative advice/help would be most appreciated. Thank you very very much.

ECTurboGSX

That sounds like the death march for the tranny. There have been a few members here that have had the tranny go in the last few months. I'd research some threads on here about that topic.

SeeKlasse

well..... did the tranny stay in one gear? if so then it is the fail-safe mode in which the transmission locks the car into one gear until the ignition is recycled. mine went into safemode a few times when my 4th gear clutchpad went out and my car would hit the rev limiter without any acceleration if i tried to gas it in 4th gear. maybe your fluid is really fresh and viscous or something? how cold was it and does it only do it when its cold out?

TuneTime

happens to me.... it could be the shifter... i notice it at night... if it starts to hang in gear i glance at the shifter and neither the 4 or D are illiminated... like its stuck between them... i put it in 3rd then back to 4th and its fine... my shifter bushing under the car is spent.... i'll be making that $12 repair soon

Kropf

Yes, my 722.631 tranny is another fresh fluid casualty!
I bought my C43 May, 2007 with 94k miles, and the 722.631 tranny was fine (no noise, shifted fine, no slippage).
At 99,783 miles and due diligence, I drained all, and put fresh M-B fluid in it. (More details at an earlier post.)

1,402 miles on the fresh fluid (while at the dealership for a windshield), tranny suddenly started making bad noises. They pulled the pan and found the fluid very dirty already and 16 short roller bearings in the pan. They said they were from between the input and output shaft. (Earlier 722 trannys supposedly had a bushing there that would frequently fail, so the rollers were the 'solution'.) They buttoned it up, and I just drove it 38 miles home tonight (about 10 miles had lots of traffic light stops).
It was noisiest when in Park or Neutral. 1st gear was also fairly noisy, so I put it in Winter mode that ignores 1st gear. 4th gear was silent - makes sense as the input and output shaft turn at the same speed.

Dealer's Service Advisor said she's seen other trannys blow shortly after changing the fluid!!

SeeKlasse said he put 1400 miles on his and the tranny blew. I wonder if the fluid had been changed just before he bought it?

I think the M-B policy change from 'Lifetime tranny fluid' to 'Yes, change the fluid' is creating a bunch of blown trannys!!!!

I'd venture a guess that my tranny would have continued on for MUCH longer with the original fluid had it been left alone. (Mine wasn't slipping at all.)
My guess is that the high mileage fluid gets thicker, which helps keep lubing the increased tolerances of the high mileage tranny.

But dump the thick fluid from a high mileage tranny and put fresh-thin fluid in it, and it causes fast deterioration of what's left of the fiber clutch packs and seals. About a thousand miles later, it's time for a catastrophe.

My warning to every high mileage owner that is going to give the tranny it's first change: Get ready for a BIG Repair!

How is one to know if the tranny has gone TOO FAR on the original fluid? I'd suggest that after the fresh fluid is put in (after a complete flush), that a dip stick (bizarre that it doesn't even have one) is used to check the color of the new fluid. If it gets dirty quick within the next few hundred to a thousand miles, get ready for a rebuilt tranny SOON! (Would another flush and fill help? Who's to know?)
If it stays nice and red, maybe you got yours changed soon enough.

(I'm shopping for a rebuilt.)

SeeKlasse

yeah i had theservice records here at my place. the car received a fluid change @ 68k, the tranny went @ 78. 10k diff but still fairly fresh.

e30t387

i never changed my fluid ive had the car for about 60,000 of its miles and it now has 84,000 and tranny is smooth and shifts smooth no noise, i dont think i plan on changing the fluid, though about it but i dont think i will.

TENNAc43

Thank you all for your advice.

The car only hangs on really cold mornings <32deg. When I get in the car for lunch everything is back to normal. I think the shifter bushing may the the culprit.

Thanks again,

SeeKlasse

yeah man my shifter bushing was broken. my mechanic replaced it when he changed out the tranny, but the shifter still doesnt shift right. he said i need to replace the shifter assembly. 425 retail. i called lpd auto (they have alot of wrecked w202's) and they have a 97 c36amg on the lot im getting the shifter assembly out of for 125 bucks... call them im sure they have alot of 5spd shifter assemblies.