Hi, I have an 02 f250 v10, and am thinking of looking at buying an f350 v10 for more hauling capacity. The price diff. appears minimal. my questions are: 1. Going from a 250 to a 350, is there a big decrease in gas milage? 2. Is a cdl needed? 3. How much more payload am i able to handle by upgraded to a bigger truck? Thanks for you help.