I would Definitely buy a 06-07 if possible.
01-02 is LB7 as well as 03 and half of 04., 04.5-05 is LLY 06 can bet either LLY or LBZ and 07 is LBZ.
The 01 though early 04 LB7 go through injectors roughly every 80k miles and their heads are not friendly for removal.
The -4.5-06 LLY has head gasket and turbo mouth piece issues. The LBZ is your best truck out of the box. That being said it has enough power stock to limp the trans if you beat it, but it makes the most power. Its basically the same motor as an LMM just in an older body for the most part.
Also I'd go crew cab and not ext because the ext cab door/cab seals are more likely to leak since they close against each other and not to the body. Ask me how I know.... showers during a car wash are no bueno.
01-02 is LB7 as well as 03 and half of 04., 04.5-05 is LLY 06 can bet either LLY or LBZ and 07 is LBZ.
The 01 though early 04 LB7 go through injectors roughly every 80k miles and their heads are not friendly for removal.
The -4.5-06 LLY has head gasket and turbo mouth piece issues. The LBZ is your best truck out of the box. That being said it has enough power stock to limp the trans if you beat it, but it makes the most power. Its basically the same motor as an LMM just in an older body for the most part.
Also I'd go crew cab and not ext because the ext cab door/cab seals are more likely to leak since they close against each other and not to the body. Ask me how I know.... showers during a car wash are no bueno.