[frodin1]

Hey there, I recently purchased an 83 Chevy truck 4X4, and I'm building a small block for it currently. I'm not real familiar with automatic transmissions and I was wondering what trans should I go with? The truck has a TH400 in it currently, however the radiator cooler breached inside, filling the transmission with water. So I believe the prior owners went and purchased a TH350 to replace it with "which is in the bed". I plan on using the truck for towing the boat and camping trips, and a little occasional lead footing around town. What I'm wondering is which of these two transmissions is the better to use, and how much should I expect to pay for a decent rebuild? Some of the locals have a tendency to do a little gouging if you don't know any better. Thanks for any input!!!

[Crosley]

A t-350 trans can not directly bolt in place of a t-400 trans or the other way around in a 4x4 application.

t-400 trans is longer, different bolt pattern on the rear of the main case, the out put shaft of the t-400 is 32 splines. There were 3 different lengths of 4x4 shafts used in a 4x4 application on the t-400 to fit the t-case adapter setup

The t-350 4x4 out put shaft is 27 splines

[frodin1]

Well I guess that answers my question then. I didn't even look at the 350, or the bolt pattern when I pulled the diesel out, so I wasn't sure. From what I was told it would bolt up, and the only thing I would have to worry about is the torque converter, and something with the regulator. Like I said, I know nothing of autos. So this helps a bit. I do have another transfer case on the 350 trans as well, so who knows what they came out of? The 350 trans is actually polished. Sure it looks nice, but I dont want to mess with it if I don't have to. If I'm putting an old style "2pc rear main seal" small block into the truck, is there anything else I'm going to have to worry about with the TH400, other than the torque converter and regulator?

[frodin1]

Looking at your post again I realized your talking about the length of the transmission itself and the shaft length, what about the bolt patterns on the engine? Is that the same pattern?