Abstract: An overhead mount is provided for disposition over a section of track along which railroad axle/wheel assemblies may be rolled and an elongated horizontal support structure for disposition transverse to the aforementioned track section is adjustably suspended, at its opposite ends, from the overhead mount. A pair of followers are mounted on the support structure for guided movement therealong and first motor structure is provided for adjustably varying the spacing between the followers. A pair of opposing abutments are dependingly supported from the followers for engaging the remote ends of stub axle portions of axle/wheel assemblies and wheel bearing engaging and pulling fixtures are supported from the abutments for shifting relative thereto toward and away from each other. Second motor structure is operatively connected between each abutment and the corresponding fixture for controllably inversely shifting the abutments toward and away from each other relative to the fixtures.