Good Morning, newbie here so please bear with me. I am looking to purchase a new F-450 6.7L Diesel V8 to haul our car wash equipment to customer locations in the Midwest. I am looking to haul a low profile gooseneck trailer that would max weight be 15,000 lbs. Payload on the truck when hauling a trailer would max be 2,000 lbs, but max 8,000 when not towing. Most of our driving is open road highway from Chicago outbound. We do however take infrequent trips to Atlanta, which would go through the mountains. This truck would be carrying a load +90% of the time. I would rather hear from experienced drivers than a couple Salesman who don't seem to grasp what I'm asking. Thank you for any help.