The LBZ started in 06. Have one in mine. Thought they only went to 07. Yes, most desirable Duramax available. Mine has 212,000 miles still runs like a dream. Average 18 all around. Easily over 20 if hiway or keep my foot out of it. Pulls incredibly well. The 6 speed Allison is awesome. I'm assuming 4wd and base model? That's the exact same truck as mine but a year newer. I paid $21000 for mine 6 years ago and it was a good deal then. Lots of them selling for $25000 and up. I would buy that truck in a heart beat if I was in the market. But I would also look it over real good first.