Abstract: A self-centering arbor adapted to locate a hole in a mechanical object having coaxial openings, such as brackets, bushings or the like, with vastly improved accuracy and repeatability. The self-centering arbor comprises two opposite free floating, spring biased, coaxial, tapered pins mounted in a housing member for engagement with the openings in the axle bracket or the like. The housing includes opposite first and second housings interconnected by a mandrel shaft. Furthermore, two spherical locating members are secured to the housing member and are oppositely aligned on an axis of the tapered pin.