Vehicle
(1) Vehicle means a locomotive, as defined in 229.5 of this chapter; a freight car, as defined in 215.5 of this chapter; a passenger car, as defined in 238.5 of this chapter; and any rail rolling equipment used in a train with either a freight car or a passenger car. (2) Vehicle type means like vehicles with variations in their physical properties, such as suspension, mass, interior arrangements, and dimensions that do not result in significant changes to their dynamic characteristics.