Hey guys (n gals maybe?) I'm from the UK (but dont hold it against me!) and new to this forum, looking at buying what you're calling a 'classic' Duramax around yr2006 but have come across an anomaly....Guy selling says its 360 hp, but his vin and rpo codes confirm its an LLY so therefore must be 300hp, right? I have done a little internet trawling for info , read some conflicting views but cannot seem to find the facts....nobody seems to be able to tell me what the differences are between the 06 LLY and the following LBZ....Kennedy diesels 'click here to mail us' doesnt work for me so cant ask him but his webpage says regard the 2006 LLY as an LBZ for tuning parts ordering so he knows the subject, just cant get hold of them for a proper explanation. Youtube is just too full of hearsayers who dont like this piston or that piston and have no reliable facts....i read the LBZ has a recast beefier block, thicker stronger rods and the piston wrist pins are bigger and read the 06 LLY has the same software as the LBZ but is detuned to 300hp....thats as much as i know......anybody with reliable info?