I dont own a horse trailer, but I trailer a boat...have you ever towed anything before? Not trying to be snarky, but its a whole new ball game. When towing, you must drive like you would if it were snowing and icy. Trucks react completely different with 2000 or more pounds behind it. Your ten hour trip is going to be a 15 hour trip towing anything behind you. Id pay someone to trailer your horse unless youve had a lot of towing experience.
Ditto that and further to it:
Hauling a boat or a race car is NOT the same as hauling live weight that can sway the trailer.
I hauled my horses from the East Coast to the West Coast, then back five years later.
Mr. WTW hauled one of the cars. He's a fantastic driver and race car driver -howeverrrr, never on this lush green earth will he pull my horses while I'm still alive. Not even 22 miles to the vet clinic. I cannot get it thru his head that he can't take tight curves anywhere near as fast with horses in a trailer as he can with his race car on his hauler.
Coming back to Tennessee in 2003, I blew the driver's side rear tire on my truck, on the OKLA City by-pass, at rush hour, in the fast lane, going 75 MPH
These tires only had 3,000 miles on them but they had sat in the California Desert sun for five years and weren't near as healthy as I thought they were
I had three horses in an open stock bumper pull. The kids were in the two Ryder Trucks and Mr. WTW was in his dually.
ONLY by the Grace of a Higher Power's guidance on that steering wheel did I get that truck across all the lanes, onto the right berm, slowed down and limped off the off-ramp without flipping us over. I have an old Heavy 3/4 GMC, ex-logger truck (not a dually) my tires are size 33's, which are way over-sized and very flippable.
My horses are seasoned haulers and nobody panicked until we got stopped and the d**n traffic whizzed by us on the off ramp like we were having a picnic. We radioed for police to come and help but they never showed up either.
Having something like that happen is rare. But the driver of the tow vehicle needs to capable of NOT going into a panic and letting go of the steering wheel. Needs to be able to make a snap judgement in the midst of interstate/by-pass/city traffic hopefully, without getting themselves and the rest of the world around them killed.
A trip to Florida is not all 55 MPH county roads where nobody cares if you take your time. The time you spend on the interstate, you are expected to be a driver than can safely "go with the flow", even in the slow lane that "can't drive 55" either.
In conclusion: My thought is to hire someone to haul your horse down if you can't start practising with an appropriately matched tow vehicle and trailer this weekend