The 5.3 from 2003 was rated at 285hp,325tq in Silverados. In 2004 it was rated at 295hp/335tq if i read right. What was changed to cause this difference. The reason Im asking is because im swaping the 5.3 out of my 04 with one from 03. Since i will be using the 04 computer will I need to do a crank relearn?