This is a lot of most useful information. I will try the suggested ways to check on the caster.
Inflation pressure: It looks like I don't really know what the correct pressure for these tires should be in this application.
I have the same make of tires (Wild Country Radial XLT M+S) on 16" rims on a '03 F-250 which calls for 55psi ft and 70 psi rear.
I realize that it's probably not the same.
What is the correct pressure for this application?