So just an update to this thread. First thing I did was replace the panhard bar with another one I had, that made an immediate improvement. I ordered whiteline bushings for the lower control arms and brought it down to the only place on the island that can do an alignment. They checked all the control arm bushings with a prybar and told me they could not check the rear alighnment until the bushings were fixed (no charge for that, they are good guys). So replaced the lower control arm bushings with the whiteline ( had to clean up the arms and make them look pretty) and replaced the upper control arms with a set I recently pulled off another 4runner in perfect condition. That made a huge difference, now the back end is tight and does not sway in the corners when you hit a bump. Brought it back to the shop this morning and threw it on the machine. Castor was just in spec and evenly distributed between the left and right. So it looks like the axle is not bent, it was just loose and moving around too much. Every road here is just a series of corners with a lot of elevation thrown on poor surfaces so tire wear is excessive to start with. I have never gotten more than 15k miles out of a set of tires. I am just going to let these wear out and see if they continue to show the same kind of wear.