Originally Posted by bmurdock
With this setup, does it look like I will have enough clearance between the top of the body and the fifth wheel trailer.
Depends on the 5er. Some 5ers are farther from the kingpin to the ground than others. To get an idea, back your F-250 under the level 5er (or an identical model 5er) and measure the clearance. If you have less than 4" clearance, then you will probably have trailer to body contact when crossing a dip as you exit the highway and go into a convenience store or some Wal-Mart parking lot. That 4" clearance should increase to about 6" clearance when you put the 3,500# pin weight on the F-550 suspension while keeping the trailer level front to rear.
I towed a 5er with my F-250 that had only 5" clearance between the underside of the 5er and the top of the bed at the tailgate when hooked up. And I had dings in the top of the bedrails where there was contact on crossing dips and gullies and barrow ditches as I exited the highway at an angle to the dip.
If the trailer has ordinary leaf spring suspension with the spring perches mounted under the trailer axle, then you can move those spring perches to the top of the axles and gain 3" to 4" additional clearance. That's called "flipping the axles" on the trailer, but the axles are not literally turned over - the springs are moved from under the axle to over the axle.
Any other comments, concerns, or recommendations would be greatly appreciated.
Probably too late for your use, but Knapheid makes a Westerner Storage body that's a service body but only 28" high. They come in a max of 60" cab-to-axle (CA) length, but your body builder could probably copy that design to fit your 84" CA.
Westerner Storage Bodies Product Gallery | Knapheide
For years I've thought that Westerner Storage body was even better for RV trailer towing than the more expensive tow bodies such as Western Hauler.
Grumpy ole man with over 60 years towing experience. Now my heaviest trailer is a 7'x16' 5,000-pound flatbed utility trailer, my tow vehicle is a 2019 F-150 Lariat 3.5L EcoBoost SuperCab with Max Tow (1,904 pounds payload capacity).