upgrading
No they did not say why Ford made the down pipe different, but you are probably right about the clearance issues.
Yes, at some point I am going to purchase a programmer. I do not know if it will be from sct, edge or banks. I only have 3500 miles on my truck now, so because of warrentee issues, I might wait until around 50,000 miles. My older 5th wheel will not fit our new truck, so we are thinking about getting a tt. When I do, it will depend on how well the truck pulls the 5th wheel or tt. If I can not maintain a reasonable speed going up hills, then I will get the power adder. Our truck is very tall in stock form. With 4x4 and camper package, it is 5 inches taller than our older truck. Our older 5th wheel is set up for the older truck and would not be level behind our new truck. Since the axles already have been moved to below the springs, there is not any additional adjustment for the taller truck. I am almost convienced to purchase a tt, because that way we could use the entire bed for stuff, like generator and four wheeler, and I ordered the truck with a 15.5k hitch that has all the electrical wiring set up from the factory.