Right now, I don't have the new tires on. Les Schwab will get them in on Tuesday, so I'll be heading over there, sans camper, later in the week. Then I'll take some measurements of various heights; such as ground to top of wheel well, ground to middle of axle, ground to top of tire, etc. I have all that both with and without the camper, so with the new wheels and tires, I can compare.
One thing I'm concerned about is that my truck, with the Nittos I have on now, handles great. I can drive my truck with the camper on twisty mountain roads faster than my wife can keep up in her Subaru. The quicker I take corners, the better it feels to be tracking. I attribute that to the Hellwig Big Wig sway bar and air bags mostly. I've noticed the body roll more or less depending on the air in the bags. I've adjusted so there is slightly more air in the right side bag than the left. Probably due to the crown of the road. But for a perfect feel and ride, I run 38psi in the right rear air bag and 30psi in the left. With no air in the bags, there is noticeable body sway.
Just to recap; I'm changing out my tires and wheels for the safety margin that is gained. I have tires rated at 3750 pounds of load each, totaling 7500 pounds on a rear axle that measured at 7200 pounds with the trailer on there.
The Toyo's I'm getting soon will have a capacity of 5510 pounds each, for a total of 11,020 pounds of capacity. The Nittos are about 4% of max load, the Toyos will be about 34% of max load. The smaller Toyo's, the 245's, would be within 20% of the max load. A 20% margin is better than the 4% I have now for sure, but for the price difference, I'm willing to experiment with the slightly larger 265's.
So stay tuned; I'll be reporting on my experience with these tires as I get 'em mounted up and tested. Oh, one thing I noticed on my current Nitto's; they took some time to break in. I mean a lot of time! They were very squirrelly for the first 3,000 miles. If I made an abrupt lane change, the rear would feel like a time lag to the front. Like how a boat feels when it's not on plane in the water and making a turn. Not a good feel! If I hadn't experience with my original tires, I would have thought it was frame flex. I'll see how these new tires feel unloaded new, then loaded new and also give them time to break in.
And don't worry, b, no strings strummed that struck a cord. Of course I took your concerns seriously, but needed a little clarification on what tippy referenced.
My hope is that the stiffer sidewall will outweigh any tippiness feeling and any sidwall roll that the E load tires I have now. There's only one way to tell!!