The best solution is to have the one you already own rebuilt! It matches the car and You know what You have! The only times I break with this is when you have non-repairable damage like a case fracture, etc. I've never yet seen any case where you are not better off fixing what came out and putting it back in! ALL parts of your car are wearing at the same rate and at the same time and this is more important than most people think.

Hello members,

I was curious about the one post in this thread how a 4-speed auto can be changed to a 5-speed with a few extra parts, well I could not resist and I called Ted the owner of transmiester last night and got this reply.
Ted told me that he had talked about doing this years ago but it was for a manual transmission only. He thought that the five speed guts from the 190 series would go into a 240d manual but there of course was no room. A 5-speed auto he said would be a total re-design for the early 80's mb's.
He had also said that the 5-speed to 6-speed auto in the 90's conversion was possible on the six cylinder versions but needed a complete electronic package to go with it and and also other parts that would make it very, very expensive.

Peter