Thanks for the advice. We ended up going to Big O. We are in Estes Park, and they seemed the best alternative. We are having four new All-Terrain tires (Big O brand) put on tomorrow. They have a more aggressive tread than the OEM All-Weather tires, and are pretty close to the last two sets we out on the truck. The tire guy said we could replace just one tire if the wear difference was less than 30%, but we just went ahead and bought new ones. I am pretty peeved that the OEM tire had such a catestrophic failure. When we got it out to look ourselves, it was obvious the inner part of the tire was busted. It was bulging and leaking air. Sigh. Hopefully the new tires last longer! It is a pain to be on a trip and have this happen. Luckily we just took a car trip here, no motorhome.
As for airing down on washboard roads, I meant those few miles of dirt roads where the road plow digs groves, like a washboard. That is always the name we gave them growing up, so maybe it is a regionalism. When we had the truck where 60 pounds was normal driving, 80 pounds on rear for towing, we found airing down to 40 made a huge amount of difference in comfort. I am not talking about running on a highway at speed, just driving 10-15 mph on washboard sand/gravel/dirt roads for 5-20 miles. Like I said, we aren?t big four wheelers, but we do like rough backroads and two tracks which is why I always had a Subaru before and now the GC.