722.3 transmission problems
 

My E320's transmission has been acting a little strange lately. First, it shudders and slips a bit in reverse when it's cold. Second, it seems to slip when shifting from second to third when it's cold also. Are these common problems? Can they be corrected by a simple repair or do they require rebuilding the entire transmission?

Ted

Your problem sounds like a problem that requires taking apart the tranny and rebuidling it. Buy a rebuilt tranny instead having someone do it becuase most likely a rebuilt willbe cheaper.

Any idea where I can purchase a rebuilt unit locally? I live in Sarasota, Florida.

Ted

Try changing the fluid first.
I would change the fluid in both the transmission and in the torque converter and see if that helps.

97 W210 should have one of 3 trans per the Russian site. 722.3, 722.5 or 722.6.

722.607 trans requires MB fluid ONLY, no equal.

No CEL?

Early 722.6's had some electronic valve body issues.

If the 722.6 a dealer can scan using SDS, see trans codes and read adptation values and tell you what is going on.

If a 722.3 you should be able to adjust the modulator to firm up shifts.

No CEL. I know for sure that it's a 722.3. How would one go about adjusting this modulator that you speak of?

Ted

Yesterday, I talked to the dealer's mechanic that just rebuilt my 722.3 transmission, about not being too happy with the hard shifts. He said that hard shifts are a common complaint for MB transmissions and, although the hard shifts don't hurt anything, I could adjust the modulator on the left side of the transmission by myself. He said that I could soften the shifts by turning the cream-colored ear counter-clockwise as long as the ear of the switch was pointing forward. If it was forward, he suggested that I turn it 180 degrees to point towards the rear; but, if the ear was already pointing to the rear, he said that he would have to do it himself because it would require his having to take the modulator cap apart to reposition it.

I did it last night and it worked just as he described. Your problem seems to be the opposite--too soft--so I guess you would turn your modulator clockwise.

At the same time, at the mechanic's suggestion, I also changed out the filter and transmission fluid from Dextron III to the expensive MB transmission fluid they use in the newer electronic transmissions ($11/qt.). Don't know if it was the modulator adjustment or the new fluid, but it seems to be working better for me now.

I would look to the modulator first if it's slipping and then catching between 2nd and 3rd. The reverse seems to be a problem with all 722s. I think it's a matter of how long you can live with it and get away without having to bite the bullet and rebuild. I had slow engagement problems in reverse for years and it finally went out completely a few months ago. I think it was a torn seal, internally.

I live in Venice and I don't know of any place that you could find a rebuilt locally. I ordered one from a place in CA and had it shipped directly to my independent mechanic in Venice. He installed it and sent the old one back (shipping for core is provided free from company in CA). It has been running fantastic since I had new tranny installed.

Rebuilt including shipping was only about $1500.

Good luck,
Frank

Frank,
Oddly enough, I ran across your old post about getting a trans. and was going to ask how things are a year later. Guess that answers that, doesn't it?

I'm going to need a new one myself pretty soon. Looks like SunValley might get another customer.

to adjust the modulator valve properly is to use a pressure gauge. too little or too much may do harm to your inner clutch disc.