1994 E320 Transmission Problem

[bentleydg]

Just bought our first MB and love it...except for one problem - it will not move unless going down hill!

141K miles, well cared for. Put some money into the usual things two weeks ago part of which included the transmission service (old fluid was very clean) and a new kickdown cable (vacuum line had a leak - or something like that).

Car drove just as well as it had been (which was perfectly). No engine or transmission noise, almost imperceptible shifting until my wife backed it out of a parking spot and put in in drive and....nothing.

PARK engages properly but moving the car out of park into any other gear and the car acts as if it is in NEUTRAL (yes the car will roll). Step on the gas and you can here the engine rev.

Fluid level is fine and the linkage is working appropriately. My mechanic (who is quite competent) can not figure this out but thinks it may be the torque converter. The transmission is out of the car.

Any ideas?

[JimVillers]

Just a thought ..... There is a drain plug in the torque converter that is removed to fully drain all of the fluid. Perhaps it was not sufficiently tightened and came out, allowing the torque converter fluid to escape when the engine is running. Sounds scary but it probably would not have damage anything.

Let us know what is found.

[Robert Goodwin]

It's a little late now that you have the box out of the car, but did it work OK in reverse?????

[bentleydg]

Jim and Robert - thanks for the replies. I will pass along the torque converter drain plug possibility to my mechanic this afternoon. I just went over and looked at it and there are no metal filings in the fluid and all teeth/splines/etc. are in their proper state. They are going to put it back in and dyno it (hopefully) with all the pressure gages hooked up to pinpoint the problem. One of the little plastic baffles was broken so they thought it might be possible (although they said not likely) that it clogged one of the inlet lines.

We will see what happens... I will definitely let you know if they are able to pinpoint the issue. I am leaning towards replacing the whole thing with a rebuilt to save me the trouble in another 80-100K miles.

Robert - reverse did not work either. It was literally perfect one second and then the next second it was a total failure.

David

[dsimguy]

I just had a simular problem with 91' 300e, driving along one minute then no forward drive. reverse still works! any ideas?

[Robert Goodwin]

dsimguy,

Now this one sounds like a B2 piston, a common failure in 722.xxx transmissions. So common in fact that you can do a Google search and find a lot of info. If you conclude that B2 is the problem and you will not be doing the repair yourself, you will have other issues. McTransmission will want to pull your trasmission and overhaul it. Dealer may not even have anyone who works on transmissions. You will need to locate an independent or dealer who has experience in replaceing the psiton. The job is done with the transmission in the car. Also remember that it may be something as simple and cheap as shifter bushings.

[dsimguy]

Robert;
Thanks for the info, I will Google the B2 piston and see if I can find futher info for this problem, and post futher results.

[dsimguy]

I found good info on the B2 piston then went about removing mine, no joy the piston assy checks out ok, but I did spot a broken band while looking up inside the removed oil pan. I guess I'll get her towed to the mechanic.

[Robert Goodwin]

At least you tried. This still turns out to be a win for you because YOU know what is wrong with it.

[inlee]

I have 93 400e Mercedes with 140000 miles, it start with very rough shifting between reverse and drive gear. Now I have slippage between first gear to next sometimes and NO REVERCE.. Any idea what is causing it?

also how much something like that cost to fix..??

any help will be appreciative.

[Robert Goodwin]

The automatic transmission is probably the least understood part of any car. Least understood by owners and many mechanics.

I have done a lot of research on the 722.3XX and 722.4XX transmissions and even rebuilt my own 722.325.

Your symptoms are beyond my personal knowledge and appear to require a professional analysis.

A dealer or good independent shop with someone who actually works on Mercedes transmissions would benefit you.

I can save you the trouble of taking it to a transmission shop. We have to remove it and tear it down. Tsk, tsk, tsk. It needs to be completely rebuilt. $3,000 please.

If you are goung to spring for thast kind of money, assuming the situation is that bad, you may want to go with a genuine Mercedes transmission. Independents can get them and unless I am mistaken, the warranty is good at Mercedes.

Perhaps some other readers can offer some other suggestions here.