not sure what its called but i was taking off my tires today to rotate them and i snapped off one of the lug nuts so now on one tire i have only 4 lug nuts and i was able to put the fifth one on but its snapped in half. (when i remove it half the stud is in the lug nut and half is still on the wheel hub) is this a major issue? do i replace the hub? or whatever its called or is it just a stud? does it matter? thanks