The disclosure relates to a high speed one car railroad vehicle that can be 500 to 2,000 feet long and is in the form of a millepede like running gear with multiple sets of closely spaced wheels and carrying load support platforms or decks for freight or the like, in which the running gear extends the length of the train and comprises a continuous center sill structure that is sufficiently flexible horizontally to accommodate curves and includes closely spaced wheel modules, each of which is provided with a pair of small diameter wheels that ride on the respective track rails, with the wheel modules being spaced so that the wheels are disposed every four feet on either side of the train. The center sill structure is suspended from the wheels by individual knee action suspensions connecting the wheels to the center sill structure, and where the vehicle is self-propelled, each wheel is individually driven by its own motor, with 100 per cent dynamic braking being employed. The wheel modules also each include a cross bearer or beam plate member that overlies the wheels thereof, on which members rest the train load support decks that are in the form of freight container receiving deck plates. The deck plates are sprung on the wheels underlying the same by employing an elongate fluid tube spring on either side of the center sill for each deck plate. The respective fluid tube springs extend the length of the respective deck plates, and each deck plate is supported only by its underlying fluid tube springs, which are interposed between the respective wheel suspensions and the cross bearers. The individual decks are pivotally connected to the center sill adjacent either end of same and rest of rollers mounted on the respective cross bearers that are oriented so that the center sill may readily shift laterally of the respective decks as required to smoothly round curves in the track.