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I bought a 1993 400 E for my wife. I was excited. She's was very much a 'buy American' kind of girl from a 'buy American' family. I'm from Europe, having lived in England and Germany. I knew a few engineers from Mercedes Benz and I grew up mucking about on old German cars- especially old BMWs and Porsches.
I know of the indestructable reputation of these cars so bought it. It has 148,000 miles on the clock and seems to use no oil (after 3 weeks of ownership). I was so excited about this car, reading up on them and educating my wife.
However the transmission had an eratic slip. It would slip on the upchange from 2-3rd sometimes. The downshift when coming to a stand still was also pretty abrupt, but as I said, it was eratic and at times it was ok.
If you manually select a gear it's ok and drive fine in that gear.
The previous owner changed out the tranny filter and fluid and the fluid is very clean and the level is fine. It engages reverse fine and promptly.
This morning my wife phoned up and told me that the transmission doesn't change at all in 'D' and continually slips (but again she manually selectted 2nd and drove to work). I'm not a whizz on automatics at all. I read that it may be the 'modulating pressure' or the 'valve body'. I also read on a thread on here that something could be adjusted at the side of the box itself.

Just for background: I'm not familiar with these cars but it never felt fast and never seemed to kick down. It should be 0-60 in 7 secs but feels slower than my Dodge ram 5.7 quad cab!

I really can't afford to dish out for a rebuild, but would appreciate any insight and helpful advice from you guys.
 

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Well if you do a search there is a stage piston that can break and cause issues that vary without the whole transmission being toast. But beyond the vacuum line that could be broken and/or leaking I would think its just getting old and needs rebuild.

Good Luck.
 

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Discussion Starter #3
Update: I drove it yesterday when I picked up my wife and the shifting problems were gone. Perhaps a slight hesitation and 'soft shift'. So it's an intermittent problem. I'm hoping in its early stages. I did some resserch for this 722.3 transmission and one possible cause is the modulating pressure is too low.

I just crawled under the car and made some adjustments as per here

722.3 and 722.416 series transmission adjustments

turning the 'T' adjustment 180 deg. I wasn't checking the pressure while I was doing it. I also adjusted the control pressure cable near the throttle. Next I'll drive the car and see if it's made any difference.
 

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I'd give it more then a 180 degree turn...you May have to pop off the plastic cap on there w/ a screw driver..then turn the T a good bit.

also, if its still slipping Type F fluid is a good way to get some extra life out of an otherwise tired trans.

Jonathan
 

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I'd give it more then a 180 degree turn...you May have to pop off the plastic cap on there w/ a screw driver..then turn the T a good bit.

also, if its still slipping Type F fluid is a good way to get some extra life out of an otherwise tired trans.

Jonathan
Thank you very much Jonathan. I just took it for a drive and I have been unable to duplicate what my wife said she came across. This in addition to before I did the half turn and the 15 or so miles I did then when I was unable to duplicate it then.
Tommorow I'll turn the T handle 3-4 more complete turns (that enough?) and in a few weeks I'll change out the fluid for this type F you speak of. Any particular brand you reccommend-Castrol, Amsoil , valvoline?

Thanks again. BTW does your shop in GA undertake transmission rebuilds?
 

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start w/ anothre 1.5 turns..that'll be a total of 6 lbs added to the modulator pressure.

Any type F...just finding it is the hard part these days.. Wally World carries it in their super tech line...again, it's worked to buy time on clients cars here!

jonathan
 

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Thanks again. BTW does your shop in GA undertake transmission rebuilds?
From previous post's, I understand he does and it's quality work.

If your close to him I would have him do it.
 
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