My truck currently has P235/75R15 Goodyear Wrangler Radial tires which are new with about 1k miles on them. I have off-roaded them on a couple of occasions at Hungry Valley which is an off-road recreation area. I am planning a trip to Death Valley this fall and debating if I should get LT version tires and possibly upgrade to 31" on my stock rig. Are the Goodyears reliable for an off-road trip to Death Valley which will have washboard, possibly muddy sections (if it rains), and rocky/rough terrain? What have been other's past experience with these tires? Good for off-roading on a long trip to a desolate location?