C20 transmission

[Tonyorlo]

I am buying a c20 without an engine or transmission. I have an early 90s 350 that I plan to use in it, and I am trying to decide on what transmission I should go with. I know the truck originally had a TH400, but would it be a bad idea to use a 700r4 in it because I may tow a car trailer with this truck in future. Im doing this on the cheap, so I don't really want to spend $1500 on a built transmission right now.

Any thoughts or opinions?

 

[1987 GMC Jimmy]

I wouldn't think it's a bad idea except the only thing is that there aren't any guarantees when you try to go cheap on a transmission, especially with an unbuilt and uncorrected 700R4. If you're sure it had a TH400, I'd actually do that for now to avoid having to deal with splines and driveshaft length since you're trying to put this together quickly and cheaply. I'd search Craigslist. If you could find one out of a Class A motor home, that would be great. They almost always have low miles. If not, see what's good in Craigslist and junkyards. All transmissions break, though, so you may just have to find a cheap core if you're uncomfortable with what you find and put it through a rebuild.

 

[Tonyorlo]

I agree with that. Saving a little now may cost me a lot down the road. Money and headaches. A family member just told me they have a freshly rebuilt th400 that was never installed. It was out of a 1st gen camaro, so I don't know if the tail shaft length could be different?

Another option, another family member has an 80s 1/2 - 1 ton 4x4 hybrid truck with a rock crusher (m22?) transmission. He wants to go to an automatic, and I am parting out a k20 with the transmission and transfer case that he wants. I will be able to give him everything he needs to go to the auto in his truck, and he will be able to give me everything I need to go to the manual in mine. Will I have any issue using the rock crusher from the 4x4 in my 2x4? I understand I will need to get a new driveshaft made. Can you guys think of anything else that may be a problem?

Thanks for the reply Jesse!