My set up and TT length

You should be fine with that truck. Mine is almost 34 and I've been all over and back in 11 years with the 5.4 wheezer. Tows fine, but short on power. My HD payload is 2200 and I use all of it. What you need to watch is your tongue weight. Not so much because the truck can't handle it, but because the hitch receiver is probably maxed out at 1150 lbs. My tongue is usually 1050 ish. I broke out my stock one and replaced it with a Drawtite. Head and shoulders above OEM spaghetti junk Ford puts on. Stiffer rear shocks may help. I do have some porpoising at times, but not terrible.