97 C230 Transmission Issue - PeachParts Mercedes-Benz Forum

Kim Langley2 · #1 07-12-2011, 09:12 PM

1997 C230
~ 180K
Transmission fluid last changed ~ 95K
Trans : 722.6

Driving home yesterday from the Pentagon [95+F] noticed that there was a new anomoly wrt tranny:

> If I'm going to sit for a bit at a light - I'll put the tranny in Neutral - when I then placed the tranny in Drive > noticeable "lurch"..

> at the end of the commute - the tranny did not want to shift out of 2-3 gear - I was at 40mph and hte revs were 4k+.. it would not shift up to the next gear.

> I pulled over > put the "w/S" in the other position - made no difference.

> I put the tranny in the #4 position - no difference.

> tranny fluid is at the proper level - measured at 80C with the correct tool

> I let the Benz sit for a while and took it around the block - and it seemed to be all-right..

Have searched the forum and plenty of issues wrt reverse - but > what's up ? why won't my tranny shift like it should??

thoughts??

glenmore · #2 07-12-2011, 10:47 PM

IMHO that is too long an interval between changes.

ATF is cheap considering, and I would change every 30k-50k. Too late for that now.

Besides at 180k, I think you are about due.

porkface · #3 07-12-2011, 11:11 PM

mercedes has changed the intervals on the same atf from never the every 40k. seems like they learned something. good luck, chuck.

mbdoc · #4 07-13-2011, 08:28 AM

There WILL be codes recorded in the trans computer.
Have them read & report back.

Get that fluid out & new fluid in ASAP.

glenmore · #5 07-13-2011, 10:46 AM

FWIW, I just had the tranny replaced in my 1991 300CE @ about 175m.

The shop owner told me that the "lifetime filled" MBZ trannies that are coming in are coming in totally thrashed. It is as if the innards were sandblasted. This he attributes to leaving the fluid with the suspended friction materials swirling around in there for an extended length of time.

He recommended frequent fluid changes, doesn't have to be the fancy MBZ fluid, just the correct level Mercon.

He predicted future problems with the newer MBZ trannies because the electronic brain part now sits in the scalding oil rather than out of it.

Will_w202 · #6 07-13-2011, 06:44 PM

Quote:

Originally Posted by mbdoc

There WILL be codes recorded in the trans computer.
Have them read & report back.

Get that fluid out & new fluid in ASAP.

And check the TCM - has it ever been swapped?

Mine had gone through 2 by that mileage.

mpolli · #7 07-13-2011, 09:25 PM

I don't think you can put Mercon in that trans though.

glenmore · #8 07-13-2011, 11:06 PM

I am biased towards the fancy Mercedes ATF also but it is not required. I have used it in the past just as I have used Mobil 1 Synthetic for the engine. Is there a practical difference? Probably not, but I think of it as a treat for the car. I don't think you can justify it based on economics.

From the Mercedes Factory Approved Service Products list dated October 2000:
(This is the same 722.6 tranny)

Castrol Dextron III/Mercon
Chevron Dextron III
Exxon Dextron III
Havoline, Texaco,Pennzoil, Quaker,Valvoline Dextron III/Mercon
MBZ fluid

Looks like just about any Dextron III/Mercon will do.

porkface · #9 07-14-2011, 08:36 AM

interesting bulletin. i have the sheet 236.14 from 2010 that does not mention dexron, just mb # 001 989 68 03 and the fuchs 4134, along with other euro only available products. don't think i would trust anything but oe in any 722.6 trans. good luck, chuck.

Will_w202 · #10 07-14-2011, 08:44 AM

Quote:

Originally Posted by porkface

interesting bulletin. i have the sheet 236.14 from 2010 that does not mention dexron, just mb # 001 989 68 03 and the fuchs 4134, along with other euro only available products. don't think i would trust anything but oe in any 722.6 trans. good luck, chuck.

Wow, are we already past the era of the 722.6 "filled for life" debacle? I must be getting OLD!

I thought this issue was settled years ago. Use only the MB fluid (Febi I think). Anything else, you're playing with fire. Do you really want to spend $4000 on a rebuild?

porkface · #11 07-14-2011, 08:49 AM

that's the point i was trying to make-oe only. not sure where the other info about dexron being on the list came from. good luck, chuck.

glenmore · #12 07-14-2011, 09:08 AM

Check your glove box. Something like this brochure comes with every MBZ car.

porkface · #13 07-14-2011, 09:15 AM

never seen that. but, i only work on them and rarely go through the glove box unless i'm fishing for a wheel lock key or a previous repair order. thanks, chuck.

Kim Langley2 · #14 07-14-2011, 08:20 PM

Update:

I have ordered 8L of the OEM Mercedes AT fluid - new filter - and will replace ASAP

I switched cars with my son [off for the summer] and he reports no issues with the transmission shifing > I'm still going to replace fluid.