Since you asked.
I run 10-ply (Series E), 12 months the year. 45-psi. I don't air down, even in hard rock (but I don't drive the Quilomene, either). I learned my lessons years ago with the abysmal quality of rock that the Idaho Dept of Lands pays for on their forest roads (hint: 1" rock would be small, usually much bigger). My truck is light, so I don't need to air up any higher than 45. The key is the tire quality.
On washboard roads I bounce and dance all day long, this is a known problem. I accept it.
