it does. its a safety issue. reverse should too! but on my 87 pick up it didnt. I firgured if the cluth was in and i put it in reverse at 40 my buddy behind me would see my reverse lights and laugh........NOPE, no lock out and i ground the shit out of the gear. I hear reverse has a lock out but i dont wanna attempt it again. i know 1st does though. BUT it is possible to go from 5th to 2nd........JUST DONT DO IT!