Longer wheel base and torque
Although I trailer a 26S rather than a 26X the problems and solutions are the same. I have made two trips to Lake Mead under the same weather conditions; clear, sunny and warm.The first trip was with a Dodge Dakota, 4x4, long wheelbase, club cab with 5sp. manual transmission, 4.0L V6 and type 3 hitch. Although adequate for cruising the flats it became winded over Malad pass on the way down and extremely so from St. George to Cedar City, Utah on the way north. It delivered 13 mpg overall fom a vehicle that unloaded had given an average of 21 mpg. Stability was excellent even when driving through the Virgin River Gorge at 60 mph, although you always knew there was a large object behind you.The second trip was with a Chevrolet Tahoe 4x4, 350 v8, 4 spd auto and clas 5 hitch. For me, the added weight, wheelbase, width, power and torque has paid off in comfort and convenience. It delivered 15 mpg overall and the only downside was the constant downshifting of the transmission through the Salt Lake City area while in cruise control at 70 mph. This would happen at each overpass. Slowing down and leaving it in 3rd would alleviate this behavior.If you're going over passes, I recommend a heavier vehicle with longer wheelbase and wider stance. Slowing down and using the proper gears will make the driving easier too. I might add that I once tried towing with a Range Rover Discovery, but after just a few miles from Jakson to Yellowstone I knew that the boat was too much for the car.