BigBen
Newbie
Im going to preface this with I don't know that much about automatic transmissions so I'd like some input on what to do. The transmission in my 89 C2500 has recently started sounding like something is rattling around in it and it drives like there is too, so sounds like it's time for a new transmission. When I bought this truck I wasn't planning on it being my daily but it now is, and I was wondering how possible it is to swap the TH400 for a 4-speed automatic. Ive heard of 200R4 and 700r4 swaps, but i've also heard that a 4-speed swap wont work because the column shifter doesn't have enough space near the transmission to move around (I'm assuming this is just for manual transmission). The upside of just putting a new TH400 in it is that they're cheaper and easier to find, but the way I see it putting a transmission with an overdrive gear would end up paying for itself as I mostly drive on the highway and I live in CA with the cheapest gas being $5/gal. The only thing I am worried about is a lower towing capacity with an overdrive gear, but I think you can install a kickdown switch? Would appreciate some input.