Does anyone have experience towing a "lite" 26' trailer in the wind? We plan to tow from Minnesota to Tucson in March. Tow vehicle is an F350. WDH is a Weigh Safe Middleweight. I am thinking that this combination should work pretty well but any experiences are welcome
24' box here with a less-capable tow vehicle than your F350. I find the "lite" term a marketing misnomer. No matter WHAT you're pulling with, these things are a big sail - and longer is more sail area. Kansas is a heckuva flatland for high wind side loading (had a few real trailer wag moments btw St. Louis and Denver), and you've got plenty of flatland between MN and AZ, with more wind as you head south. I've also drug a 40' trailer with a Chevy 3500 Dualy up and down IL and MI highways – plenty of flatland there, but not as much wind as Kansas and Oklahoma.
You'll definitely feel aero impact from the trailer, plus bow wake from semis, and side winds, but the
heavier tow vehicle and slower speeds will be your friend. Your trailer functions as a 3-ton, 26' long lever, and being bumper-towed decreases vehicle stability over, say, a fifth wheel/gooseneck setup). But, properly setup (Weigh Safe makes a good product) and careful towing and you'll be fine. Not a bad idea to watch wind forecasts and be ready to sit out higher wind events - it does get bad at times. Don't discount driver fatigue, either - get off the road in a rest areas if you need a break.
I am thinking that towing with a full fresh water tank might be a good idea. Extra weight and down low.
I'm not a "tow with full tanks" guy, mostly because how tanks are secured in place (as in, not very well). The trailer is already plenty heavy. Increasing weight by 430 lbs (54 gal * 8 lbs per gallon) won't make your trailer more aerodynamically stable, but it will increase the force that the trailer can/will have on your tow vehicle (lever arm being increased by the distance from the ball hitch to the water tank). I'd be of a mind to load in 5 gal of water for overnighting or potty stops and call it a day.
I might be a little leery of state roads vs interstate - there's
not much time or distance difference between the two for your intended route. State roads mean less semi traffic, but definitely more time through small towns, less direct routes, potentially poorer pavement and more potential backups without necessarily giving you coverage form the wind. Interstate means more traffic (and definitely more semi's) out there with you, but the route will be more direct, you'll have access to gas/services that will accommodate your rig's size, and - if there's trouble - you're more likely to be able to get attention faster. Either way, put a good road kit of gear together for your long drive and you'll be good.
You're a seasoned veteran and know what you're doing - just take it easy, keep your speed down (despite how strong your truck is), and enjoy the trip.
Just my .02/hope this helps. I could be - and often am - wrong.