cblodge42

I'm new to the site, sorry if this post isn't in the right place. After days of searching I can't find the answer to my question so here I am. I need a new motor for my 2008 silverado 5.3 lc9 (Vin, 3) Is there a difference between the Vin 7 and Vin 3 lc9's? And if I were to get the Vin 7 would it bolt right in with no tuning needed? Also if I were to get a newer (2010) Vin 3, would I need to reprogram to go from the 6 speed to the 4 speed tyranny? Thanks in advance for any help!