I like my 19.5's on my 2005 Ford. They changed the chassis and front end design compared to yours. We rarely use the truck empty, that may also be why we don't get beat up - It's always towing or hauling something. My 245/70R19.5 PD890's did well last season over Stevens Pass but I do have to be careful in lose sand.
I had 265/70R18 Michelins before the 19.5's. They rode well empty and loaded, but were too close to maximum rating when I am loaded and hitched up at the same time.
I would probably want to regear to run your 35" tall tires with my load. The 33's are just about right and my stock 31's let the engine rev more than it needed.
