While I cannot comment on a Ford or any late model gas 3/4 ton, I went from a 2005 Chevy 1/2 ton with the 5.3 to a 2011 Chevy 3/4 ton with the Duramax. I tow the same sized trailer as you do, and have driven the same roads with both rigs.
While the 1/2 ton made it through the mountains, the diesel is so much more capable it isn't even close. Where I struggled to break 65mph in a headwind on I80. I can walk away from the trailer as fast as I dare with absolutely no signs of struggle with the diesel. Hills mean nothing, and with the exhaust brake, going down is a stress free event. I am sure a 3/4 ton gasser would have done the job well, but I doubt it would be anywhere as nice as the diesel.
I tow about 5,000 miles per year, mostly in the summer on long trips. The rest of the year I am a bit 'over trucked' but I don't care. The diesel makes a great daily driver as well. Although the price is higher than the gasser, I plan on keeping the truck for a very long time, so it was worth it to me. Even if it is $10,000 more, if you keep the truck for 10 years (my plan is to keep it longer than that) you are only paying $1,000 per year more. Pair that with better mileage, and the diesel starts to make sense if you tow a fair amount. Maintenence cost is a bit more, repairs should be less frequent as you are not stressing the truck as much, and resale is better. Good luck with your choice.
Last edited by K1500; 05/25/13.
