Ok I got my truck and the engine locked up and will not turn over. I took it to a mechanic and he looked at it and said the motor was toast. He did get the engine to turn over but it knocks. Does anybody know what are the possible problems might be without having to tear apart the engine. I am pretty sure its going to require a massive rebuild...or should i buy a running junk motor?

You are probably going to need a crank kit(new crankshaft and main and rod bearings. My dad ran up on a great deal on a B2 one time(besides mine) it was an eddie bauer 4X4 and he got it for 200 bucks but the engine rattled and knocked severly. It was a total rust bucket that he just wanted to use for hunting. He didn't want to pull the engine to do the crank kit(my dad is ASE certified mechanic) because all of the exhaust bolts and just about everything else was so rusty. He just took the motormounts off and jacked the engine up enough to pull the pan but not enough to get the crankshaft out(not enough room) so he just bought a main and rod bearing kit and no crankshaft and just installed the bearings. He traded it later on for a rifle and the guy is still driving it.