I have a 2000 GMC Sierra 1500 4x4 with a 4.8l v8 that has well over 240,000 miles and starting to have issues. I'm wanting to upgrade to a 5.3 or a 6.0. I have found a lot of information on this site to help in that decision. However what I haven't seen and need with is the VIN number. When looking at crate motors some say they will only fit models with a certain letter in the vin, I find most common the letters T and Z. Mine is V. Can anyone explain this to me. Thank you.