Ford wanted to soften the ride of the explorer so asked tire manufacturers to deliver a tire that would run at 26 lbs air. Firestone is the only one that would, everyone else said NO. The problem came when pressure would drop a few lbs the tire would overheat and blow out. The short wheel base on the explorer made it prone to flipping. The truck only flipped when a tire blew and the Firestones were sold to Ford with a factory approval for 26 lbs but they were marginal at best. The tires WERE failing when inflated to the factory spec of 26 lbs.
Ford now says to disregard the pressure label on the door and go by the tire mfg's rating of the replacement tires. Guess they decided 'ride comfort' wasn't so important in the long run . At least this is how I understand it (I own a 1998 Explorer and inquired about tire pressures at a Ford dealer).
U-Haul has a company wide policy to NOT rent trailers to Ford Explorers but will rent to Mercury Mountianeers which are dimensionaly the exact same vehicle.