Thanks Guys...
First..when the engine crapped out..just before it happened,, there was terrible clicking noise, then a BANG, then nothing. The engine won't turn over so there is nothing to diagnose I guess (according to the GMC dealer). He says the engine is frozen.
He wants $5800 for a used 70K motor plus $2 thou. installation. OR $6200 (maybe $6500, I forget) for a new engine from Japan..PLUS the $2 thou installation.
Thanks to Ldub I found 6 possible engines all under $3 thou. But the problem now is getting them to the GMC dealer...or maybe I should have the car flatbedded to where the engines are.???
I know this sounds STUPID but I never thought to look for an Isuzu dealership in the first place. I haven't seen a new Isuzu anything in years.
I live in Albany, New York. The used engines are in Pa. and Brooklyn NY.
I'll check for any Isuzu dealers and let you know whats going on.
In the meantime I thank you all for your advice.