As long as it is stock and hasn't been modified by a PO, it should have a 5 on 5.5" pattern (that's 5 lugs on a 5.5" diameter bolt circle). If the PO got creative you are going to have to measure. For an even number of lugs, you just measure from the center of 1 stud to the center of the opposite stud. To get a close indication of the size of a 5 lug pattern measure from the outside of 1 stud to the center of the third stud.