wich Transmission to pick? 350, 400, 700r4
 

Anyone have an openion on which Trans to get? I have an 87 full size blazer 4X4 with a 350 5.7L
I want something that will hold up and help with bottom end. I am sitting on 37" tires right now. I think that my 350 trans just crapped out on me today..

The 700R4 has a better 1st gear ratio and the benefit of overdrive. They can be made to handle good power too, but did have some flaws in stock form.

Are you sure your truck has the TH350 now? If so, switching to the 700R4 would be somewhat of a pain and the TH350 can take some abuse if built up right as well.

IMO, there is no reason to go to the TH400. It is just over killl.

What if someone wants to sell you a TH400 from a mil spec blazer for $200? A buddy has one he was going to use in a Jeep but changed his mind.

Hooligan, where is the tranny located? will he ship it??

I have a TH400 under the barn that I was saving for my Chevelle if I ever go big with power (turbo/nitrous). It was free, but you have to be pushing big power to get over the parasitic loss. All that strength comes at a cost.

also. a th400 is longer then a th350 so you will need different driveshafts, have to move the crossmember, and your transfercase will not work on the th400. the output shaft is bigger and has more splines. also you will need the electric kick down switch and bracket for the gas pedal, those are easy to find in any junkyard

edit... it is POSSIBLE to swap in the smaller spline output shaft into a th400 if your gonna rebuild it anyways. got a truck that someone did that too.

I think that I will swith to the 700r4.. I like the idea of 4 speed plus OD.. I reall like the idea of the lower end... What conversions do I need to expect going from the 350?? I think I found one..