I bought a 1983 all original GMC Sierra with less than 50,000 original miles. While driving home, it stalled, and will not turn over. The transmission has overdrive on it. Before it stalled, I thought the transmission was vibrating.

My Question: I don't know how the TC lockup wirked on the old trannies. Is it possible for the transmission to lock up the engine so it won't turn over, or do I assume it's the engine itself (305)?

Thanks.

 

I do not know much about this year of the trucks, but I believe the tranny was the TH350 which was a great tranny. I do not know about it locking up though. It should not be able to keep the engine from completely turning over though. If it did somehow get "locked in" the motor would still try to turn I think. I would probably look motor 1st. You could try jacking up the truck, puting the tranny in N and see if you can move the driveshaft by hand. Then try to move the front pully bu hand tthis should at least give you an idea what is freeing up. Again I cannot inagine that the tranny would lock up the motor.