i have an 03 5.3 if i plan to get a 6.0 do i want to get a 03 or newer or will they all bolt right up to my trans?

 

Well, you only need to get an '01 or newer to bolt up, but if you have the opportunity, I would get an '05 or newer if your looking at an LQ4. The '05 and newer LQ4's got the beefier rods with floating pins and coated piston skirts. Now if your picking up an LQ9, it really doesn't matter which year you pick up.

 

you will want to get a 01 up with aluminum heads the 99-00 with steel heads will not work because they have a longer crank if it were me i would look for a 03 up just so you dont have to deal with the piston slap

 

my 02 lq9 has no piston slap. Back when I was looking for a motor I made a big deal out of getting the beefier forged con rods. In retrospect, I don't think it matters. The standard 6.0 rods have been proven over and over to be plenty strong.