Alright, This upcoming summer im going to switch out my 305 from my 87TA and put in a 350. my car will have around 130 thousand miles on it, i have changed the tranny fluid when i got it so that has less than 2K on it. But once i put in the new motor i dont know if its going to tear that Tranny and Rearend apart. i have the TH-700(r4?) transmission. my buddy has a 92 T/A with a stock 350 and same Tranny and his just went out at 120k so i wonder if i should save another 1000 to get it re-built or just see how long it goes... and what about my rear end, i know nothing about it. any ideas and thoughts would be nice! thanks

 

Definitely have it rebuilt. just make sure they put a good shift improver kit (Transgo) in it, as well as all the necessary upgrades.

 

You can have it rebuilt if you want, but I would leave it alone unless it is suspect from constant abuse. My tranny had 204,000 miles on it and worked behind my 425 hp 383 for a while. The only thing I had to put in it besides bushings and shift kit was 3-4 clutches. Of course I rebuilt everything, but that was all it needed. Use your best judgement, if you don't have the cash right now, go easy on the tranny until you do, it won't blow up.