I'm about to pull the transmission off of my 1992 400E with the 4.2 v8. A few months ago the car started acting strange with the reverse gear only. It was making strange noises, then completely stopped working. I have searched the forums and found that many people are saying that it's the reverse clutch. I have a complete overhaul kit with clutches.

My concern is a technical bulletin I found http://www.europeantransmissions.com/Bulletin/DTC.merc/97-20.pdf

Basically saying that if there is no reverse then the problem is a accumulator switching on control valve or the accumulator switching on piston... thats found in the valve body.

What parts do I need to make reverse work again? I've looked at shift kits, but I think those are for the forward gears only? Anyone with any expertise or knowledge on this would be great. I've talked to Phil at peach parts and Roy. Thanks in advance for the help!

Think of it this way - if your reverse clutches are worn out the media from them is in the valve body, it would need to be cleaned out YES: soo take out the valve body see if your trans has this one in a hundred problem ( MY OPINION ONLY ) that the link talks about

You have nothing to loose but time - if its your only driver than you may just want to go the gusto and over haul it but dont forget the valve body -- jz

thanks for the advise johnjzjz.

I don't want to pull the trans out and find out I need more parts and have to sit on my butt for a week waiting for the parts to come in... although I know I may have to do that anyway. Why do you say it's only a 1 in 100 problem?

valve body issues are almost never, dirt from other issues in the trans is a normal cause of a valve having problems. if the car had 3000 miles than yes the valve body is a suspect -- jz

the drums have O Rings under the piston guide that are not in the normal kit, and MB does not show them at all, if a problem comes up ( dropping out of 4 th or reverse issues SOMETIMES < not all the time -- they expect you to replace the drum ( 6 /7 hundred each ) BUT a kit is available for this repair it intalls a drilling of the riverts in the drum removing the piston ( Note you must funnel drill the piston so as it is not held up ( reducing clutch pack clearence ) it is all in the spceial O Ring kit directions,

The o rings under the drum that is steel are heat damaged over the years ( they dont move at all just sit on the one spot ) and turn into stone, than a massive oil internal leak starts to happen when the gear that uses the clutch in employed high gear in some cases does not even engage after a rebuild < we have fixed many units from other Repair shops that could not figuer this problem out -- if you do it yourself i believe i have good set of directions about the drum O rings -- jz

My 92 500 SEL with the 722.370 trans started clicking in reverse about 90K, I took it to the dealer and they did not find any residue in the pan. This continued for about a year maybe more when it started to lurch and hesitate going into reverse when hot. The opinions from various shops was "front clutch", back to MB again and they confirmed the opinions. They dont rebuild transmissions, so a MB factory rebuilt $3,200, 2 year 24K mile warranty, it did not need a converter.
btw, that trans is a handfull if you dont have the proper tools to help you

My 722.3 is having a similar problem... reverse took longer and longer to engage, then quit alltogether. I'm expecting to find something like this when I take it apart: http://www.peachparts.com/shopforum/showthread.php?t=254000

-Jason

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

wow they left a 100,000 mile convertor in it ( having said that i have yet to see a MB convertor fail but we have them gone over when we do a complete for that kind of money -- and high miles

reason they only do a core swap is the seals are not serviceable according to them MB - and no matter what some think the dealers do not want high end techs they cost too much to keep on hand --

and you are correct its not for a novis but if 3 thousand is out of the question than they do sell a book and their is info on doing it - jz

I agree with you John, they ordered a converter, but decided against installing it. It would have been a piece of cake at the time the trans was out, and it was on the work ticket and then credited out?

I'm having a hard time getting the transmission removed from the car. I need a manual. Has anyone found a rebuild manual for a '92 400e 722.354 transmission? My problem is the exhaust. It's got come out in order for the transmission to come out. Anyone have any experience with this?

The book is available on CD i got one than took it to staples and had it printed out on paper than put it into plastic and than into a binder --

drop the exhaust at the hedder pipe if you must

Here's the link to the best 722 tranny manual I have found:
http://w126.pp.ru/akp722.pdf

My reverse started clicking and engaging slowly in reverse, and indeed it was just the reverse clutch plates. I did find plate material trapped in the filter when I cut it open.

The rest of my tranny was working fine, so, since I was doing the R&R myself I opted to just go far enough into the tranny to replace the reverse plates.
Getting that far is really pretty easy, and no special tools required.
Only problem was getting the band spring back in - you have to push hard and turn the plug screw at the same time - a little ingenuity with a large wrench as a lever got it done. I found no residue in the tranny other than in the filter, so I just buttoned her back up, and all was good again.

DG

Thanks S-class, this is good news. I'm taking my sweet little time, but it's always good to hear success stories

I'm planning on replacing all clutches and having the torque converter rebuilt as well. I've got over 200,000 miles on her, so I don't want to have to pull the tranny again anytime soon. I'll take some pics and post them up with my progress as I move along.

go to the specialty convertor shop that does this kind of work hand them your convertor and tell them you want it back the same one

convertor overhaulers buy junk units that have been in high speed crashes and alike and no telling how bent it might be

have them do your known unit -- jz

awesome I found a local shop that will rebuild my torque converter for $132. Sounds ok to me.