Hi to you all,

I was just wondering what could cause a transmission to fail shifting the gears when you are trying to go slowly (not gunning the gas pedal). My vaccum is ok (replaced modulator and verified lines) and everything seems to be working is there something in the transmission controlling lower speed shifting because my car starts off in 1st gear from a stop where as it should start in 2nd normally and downshift to 1st if the pedal is floored.

Im starting to get really sick of MB auto trannies to the point that id say NEVER AGAIN to an automatic

Car is a 190D 2.5 86
Tranny just fixed 2 weeks ago (governor, valve, a few gears - no warranty on job)

Anyone who knows what could go wrong in these transmissions is more than welcome to share

Is there any illustrated exploded view of MB automatics on the web as well ??

I am sorry to hear of your problems, but I have to disagree with your header, " MB transmissions suck"
I have a friend with over 400,000 miles on his original automatic. Another friend with over 250,000, and mine has over 240,000 miles. On the otherhand, Tauruses' seem to die in 70,000- 80,000 miles on average, ( I have one with 125,000 miles, but its starting to slip, and I change fluid regularly).
I would suggest finding a GOOD ( read non franchise) shop who knows these trannys and let them tell you whats wrong.

I am not an expert, but here are a few things:
It could be a bad kick down switch, or whatever MB calls it.

Could be a slight chance it is the Tourque Converter. A few weeks before mine went, it was slowly starting to do screwy things. Starting out in 1st gear was one of the things that it did a few things. When it went all the way, I had a hard time to getting it to go. The front pump also went out, so that was also part of the problem.

I have to agree with MS Fowler on this one. I've had many problems with my Mercedes transmission as well, but it all comes down to having people who don't really know what they're doing work on it. My wife's Taurus started having tranny problems at 30k miles. Now if you want to tell me Ford transmissions are crap, I'd be inclined to agree with you.

__________________
Dave
1995 C280
1999 Triumph Daytona 955I - my speed fix.
1982 300TD - Gone, but not forgotten.

Go here and download the 2 pdf files at the top.
It is a factory manual for the 722.3 transmission found in G-wagen, yours is almost identical.

http://www.g-class.ru/repair/automat-722_3-001.shtml

It is good reading material.

__________________
/Per

MB E300TDT -98

Hey 123 i think ur getting very close to my problem
Just before it started to do that i heard a sort of a fluid leak inside the tranny and when i got under the car it was coming from the front of the tranny (torque converter area). After taking it out of the garage where the mechanic did the work i replaced the kickdown solenoid but it worked normally for a while. So im starting to think its either that solenoid or the torque converter that is causing all this.

Concerning the longevity of MB trannies, They will last long if you dont push them and if you never exceed 100 km/h on the highway. I drive my car like a maniac usually doing 150km/h on the highway Its ment to be driven and i drive it
So there i said it.. for agressive driving.. MB autos suck

Does the car make a thumping noise? That's what mine did. If you have to start reving the engine to get it to engage, then you need a tourque converter. However, if you say you replaced the kickdown switch already and that fixed it, then you might want to look at it again. There might be a lose connection, which would be a simple fix, or you have a faulty switch or you have another problem that is caused it to go bad.

On that same transmission? Sounds like it has served its engineers well to me and is as far as a feminist from sucking...

__________________
1982 Mercedes-Benz 300CD
1982 Mercedes-Benz 240D - stick

It's sounds like it could be the tourque converter. Here is what you do, check the kickdown solinoid, and make sure everything is the way it should be, and fix any problems. If that doesn't fix it, take it to a reputable transmission shop, and have them take it on a test drive. Most shops can should do this for free, and they can tell you what is wrong. It shouldn't cost more than $600 to have the tourque converter replaced at a good shop, but half that amount if you do the work yourself.

To 123

No it does not make any thumping noise it engages just fine its just that i have to make the engine rev until it changes gears.. it just wont shift gears when i just try to drive it slowly. The noise that was coming from the torque conv. was soudning like a pressure hose leaking.. but internal if you know what i mean.
An open circuit for the kickdown would make sense however.. i will check into that tomorow. Kickdown was working fine after i replaced it but it might have let the ATF pass trough (all the kickdown is : just a relay which opens and closes a channel for ATF to pass)

For the other comment
No this is not my original transmission
I bought the car with a faulty one.. managed to fix it, drove 20 000 and it was completely burnt, then replaced with rebuilt by mercedes benz, lasted 3 yrs or 50 000 kms and its giving me a hell of a problem again.

I have the S.T.S.G Techtran Manual for the 722.3 and 722.4 transmisons. If You need it please post I will let You use same. Pls return.

__________________
82 300SD
93 F250 4x4

I don't know if the 190D is a second gear sitter or not (sits in 2nd, downshifts into 1st as soon as you open the throttle) -- this is normal for the older diesels, but my 87 300D starts and sits in first, as far as I know.

MB trannies normally last 250,000 miles in 'normal' german use, which is pedal to the floor most of the time.

If you have trouble with burning tranny fluid, change to synthetic and add an oil cooler, but I simply cannot figure out how you can roast a 190 D tranny even with hard use -- no power!

How often do you change tranny fluid? If you are going to drive the guts out of it, change it every 20k miles or so, drain torqe converter, change filter.

Sadly, erratic shifting is a sign of a dying tranny as long as you KNOW the bowden cable is adjusted correctly -- on the 60x engine, it must be just all the way out of the housing at idle, no tension on the spring, but no slack, either. Make sure the while plastic adjuster isn't broken -- they get crumbly with age, and the threads can strip off.

If the cable is pulled into the housing too far, the tranny won't shift up at very light throttle because it is being signaled to hift late. Too loose, and it upshifts too soon at wide throttle.

Missadjusted bowden cable and/or vac system cam cause the tranny to slip, and that burns the clutches and fluid.

As far as life, my 31 year old 280 SE has a three speed auto, as far as I know the original, and it works perfectly at 165,000 miles (plus whatever mileage accumulated while the odometer didn't work!).

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Thank you all very much for the help

Unfotunately i havent still figured out whats wrong with my tranny
Tried to replace the kickdown solenoid as i thought the circuit might be open and not allowing the tranny to shift sooner but it did not solve the problem.

What im thinking is completely disconnecting the bownden cable from the throttle to see if it will start to shift sooner. The tranny has already an oil cooler and yes i do change my fluid and filter regularely.

Thing that puzzles me.. just after i got it out of the shop the tranny was working marvelously. AFter i adjusted the modulator a one small tick to shift smoother, then things started deteriorating first.. 3rd to 4 came later then 2nd to 3rd and now its beggining from 1st every time (should begin in 2nd when not pushed hard) Just before this happend i heard a high pressure liquid leaking sound inside the tranny (towards the front where torque converter is) could that be a secondary pump failiure??

Because upshifts are fine with no flaring but its just shifting rather at redline when the car is not even pushed.

Does that 190 have a turbo? If so, your boost control/tranny circuit is leaking. Make sure you don't have a leaking set of vac transducers for the turbo and EGR valves, this will cause low enough vac to make the tranny bang HARD and usually also prevents the AC from working correctly (no center vents, no floor heat)

Shift must be rather frim by american standards -- if you cannot feel it thump a little when it changes gears, it's too loose, and will slip enough to burn the tranny fluid.

If it was working fine when you got it back, you probably should have left it alone, sadly. I've never been bothered by firm shifts. Note that if you also have bad engine mounts, the engine with bounce and really make a loud thump -- so will a vac leak so that the shifts aren't softened at light throttle.

If you had a vac problem (unlikely if a good shop worked on it) and you adjusted the modulator to give smooth shifts, you have just burned the tranny up from slipping the clutches. You would have to set the modulator VERY soft to get it to shift smooth with no vac on the modulator. How many turns did you make on the T?

Make sure the cable is OK -- it goes INTO the tube when you open the throttle, rather than the more usual pulls out when you open the throttle. There is enough adjustment there to get you into trouble. On the 300D, it was pulled in quite a bit to cover up the harsh shifts from a vac problem, with the result that it wouldn't shift into fourth below 40 mph, and would hang in second forever at light throttle.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

No turbo on my car
Vac is fine i tested it and changed modulator thinking its bad
And all that i said above happened in range of 200 km and it is impossible that the tranny is burned
I adjusted the Modulator turning it only 1/4 turn that was about it.. it did not soften shifts much they were still harsh.. i do not like it to flare anyway. When i adjusted it, the tranny did not flare when changing gears in Kickdown position so i assume the adjustment i made was not enough to burn it. Adjustment cable hasnt been touched since original.. and it is adjusted fine i checked it.

Im still staying with impression the guy who did the job left his hands on my tranny.