2005 F-350 Chip Question

Hello all, been awhile since ive been here, but I have a question, ever since my dad bought his 2005 F-350 cab and chassis truck, (flatbed now) he has been conplaining non-stop about how theres 0 low end on it compared to his Dodge. The other day on the way home from work we approached a very steep, low speed hill. We didnt have much of a load on it, a small trailer and an Ls170 http://www…0LS170.JPG anyways, the truck started to bog and eventually stalled. We had to throw into low and slowly, just barely creeped up the hill, the truck just wanted to die the whole entire time. My dad said “that does it” and he sent me to the computer to find the absolute best chip available for his truck. Any suggestions?