denisgav

Hello everyone, a while back I started a project where I swapped the powertrain from a 98' S420 into a '96 and I got some really great help from this forum, here is a link to the original thread http://www.benzworld.org/forums/w140...ibility-3.html. Since then I've been very busy with school and opening a body shop so I haven't touched the car since I completed the swap but I'm leaving across the country in two weeks and would like to leave this car as a gift to my father before then. Currently the car starts and drives fine until it come time to gears, sometimes it doesnt shift up or it doesnt downshift when I give it throttle. I put in the '98 TCU because with the '96 TCU it would take a 4-5 seconds to actually kick into gear after I've selected drive. One of the contributors here, Mava, suggested early on that I may have to swap the valve body in order to get the trans to run correctly so thats what I am trying to figure out right now. When the car had the old ('96) powertrain, the transmission would shift rough and sometimes slam shift at higher speeds so there was already something wrong wit it to begin with, possibly with the valve body. Because of this I dont want to just throw the '96 valve body into the '98 trans and see if it runs. To clarify, I have essentially no experience with the inter workings of an automotive automatic transmission but I am mechanically inclined and have done plenty of engine rebuilds and such. Can anyone throw out some ideas of what direction to take from here? valve body rebuild? is that even possible? have scientists yet figured out what that gray matter resembling maze of oil passages in the trans actually does?

oldsinner111

did you reset trans?

denisgav

How do you reset the trans? I did swap the whole TCU and the battery was dead for a while, would that reset anything?

oldsinner111

go to benzworld,there are write ups on how to do it.