jack up the tire, put your hands at the top and bottom and shake hard (alternating in and out with your hands). does it move? now put your hands at the left and right and shake hard. does it move? if you push in and yank out on the tire with your hands in unison, does it move? then reach in and shake the axle shaft. does it move? try rotating it. how about now? if you rotate the tire does the axle shaft move exactly together with the tire?