I bought a 1983 all original GMC (http://www.truckforums.com/m_12033/tm.htm#) 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 (http://www.truckforums.com/m_12033/tm.htm#) to lock up the engine so it won't turn over, or do I assume it's the engine itself (305)?

Thanks.