stock rear, haven't changed the wheel bearings during my ownership, aluminum ds under 10k, tko-600 trans under 10k, should i just change the gear oil in the rear, if so, with what additives and fluid? How can i check the wheel bearings? going to see how loose/tight the ds is, i had it loosen up on me, but torqued it down extremely well. bought locktite for it this time.