Been looking for a cheap aluminum block LS to swap into my 300zx. Leaning towards the LM4, I searched areas for Trailblazers, Envoys, Rainiers, etc. Well, the majority of the ones I saw being parted out or sold cheaply all mentioned "blown motor". They didn't go into detail, though. Now I know GM only made them from '03-'04... was there a reason?