A sensor system includes one or more sensors that sense vibrations of a vehicle and one or more processors that can determine a speed of the vehicle and determine whether the vibrations occurring at one or more frequencies of interest (that are based on the speed of the vehicle) indicate damage to a propulsion system of the vehicle. The one or more processors optionally may determine a hunting frequency of a wheel and axle set and/or a lateral acceleration of the wheel and axle set from the vibrations. The one or more processors can determine a conicity of a wheel in the wheel and axle set based on the hunting frequency and/or the lateral acceleration that is determined.