I've seen two Ford 1 ton dually's throw oil out the front bearing on their auto trannies maneuvering around in the campground. Even if 4 WD isn't needed just shifting the transfer case into low range makes maneuvering a snap. Especially backing into an uphill campsite which is what both were doing when they blew the seal. The one time I backed in the campsite beside them so effortlessly that the owner of the dually wouldn't talk to me. The other happened at an Ohio RV.net rally. He had 4WD but didn't use it until the seal was already history.