Ok, I have an 08 F-250 Super duty. I love the truck, V-10 and all. I pull a 5th wheel camper through the summer as well as using it for a daily driver. Biggest problem I am having is the really rough ride. I know, it's a heavy duty truck, but damn, on the back roads it is a beautiful ride, but hey on the interstate at 80 mph, it will rattle yer teeth out! It feels like I'm on a bucking bronco! Shocks? Tires? I don't know, and it is expensive to just start replacing tires! I run 55 psi all the way around, hankook Dyna pro 10 ply tires. As far as I know, the shocks are stickers with 107,000 miles on em. Help, any ideas or explanations welcome!

 

I would look at the shocks, your truck is 12 years old with 107000 miles on it, if original they are quite likely bad.
Does it drive better with or without the trailer attached?

 

I am sure that shocks could do it, but my tires (GoodYear DuraTrac - load rated E) have been prone to belt separation and that will sure cause a rough ride at higher speeds.

That said, a close inspection was all it took to see the "bulge" in the tire.

 

Springs have the biggest impact on ride quality than any of the items you listed, except for bad roads.Shocks just control spring oscillations and unless they are leaking or bouncy, replacement will provide a little improvement only but with over 100k on them, they likely are worn out. Your tires could be overinflated especially if you are running"max" pressure as listed on the sidewall..