Abstract: Method and apparatus for truing metal wheels of railroad locomotives and other rolling stock without removal of the wheels uses automatically controlled mechanism carrying a cutting tool and disposed in an open pit below the wheels which are lifted from removable rail sections for the truing operation. In preferred embodiments of the invention, the wheel to be trued is independently driven and the cutting tool is mounted on a powered cross slide which is controlled by a conventional tracer control unit which causes the cutting tool to remove metal from the wheel to form a wheel contour corresponding to a preestablished pattern.