i believe they were called exploders because when people were driving down the road at sayyy  45 mph, and tried to put them in 4wd, something having to do with 4wd(transfer case, etc) would get wrecked. so ford started building these parts out of plastic, and then when they did this, they would just explode and it would be much cheaper to repair. at least thats what my auto shop teacher said a while back lol