Have a '79 maybe, Custom Deluxe 3/4 ton plow truck. Am putting a t350 in, from maybe a 82' 1/2 ton PU, and used the torque converter from the 3/4 ton.

Once tranny was in, it revved way up and would not put engine power to tranny, and could barely drive. Dropped tranny this am, and the 1/2 ton Torque converter is about 1/4-1/2" smaller, only has 3-flywheeel bolts VS 6 on the 3/4 ton.

Someone said problem could be lack of fluid in the torque converter, but it poured out fluid as I removed it from the tranny. So I don't think it is a fluid problem in the TC. I didn't fill it beforehand last time, didn't even know I should. But t had plenty of fluid in it this time

Now, should I put the smaller TC on and hope that is the problem, or can I check a TC to find out if it works beforehand? Is there some other thing to check? Could TC have gone bad?