Haven't heard anyone mention the use of load leveler or stabilizer arms, that appear to be commonly used on camper trailers. We started using these when I was a kid, on the camper, and I would think they would be great for any sort of heavy trailer. I've seen many rigs around here, sagging in the back, even though they we not overloaded. That kills steering, handling, and braking in the front.
For those who don't know (maybe some one could put up a pic or better explanation), the stabilizers are usually slender solid steel pieces about 1" or so square, about 30" or so long. They bridge between either side of the receiver hitch (you need a special hitch with the "sockets" to accept the stabilizers), and back to the trailer tongue frame on each side, where they are tensioned in the same way a chain binder is. The solid mounting at the receiver, and upward tension back along the tongue, forces the tongue/hitch/truck frame up into alignment, and puts more load on the front axle. I'm told it's possible to put enough force on the stabilizers that you can actually reduce rear traction, if the ball is too low to start with.
Once properly adjusted for the truck/trailer, they are very easy to put on and pull up. Can anyone give more detail on these, and possibly any problems or concerns? I'd think a lighter truck, like the Toyota, would benefit greatly from them.