1. A method of evaluating a railroad vehicle, the method comprising: a computer system acquiring vibration data from a plurality of vibration sensing devices located at a plurality of locations along a length of at least one rail along which the railroad vehicle is traveling; the computer system generating enhanced signal data from the vibration data acquired by the plurality of vibration sensing devices; the computer system evaluating the enhanced signal data for any anomalous vibration features detected by more than one of the plurality of vibration sensing devices at highly temporally coherent times as compared to variations in vibration features due to background vibrations caused by the railroad vehicle traveling along the at least one rail; in response to identifying a plurality of anomalous vibration features in the vibration data, the computer system evaluating the plurality of anomalous vibration features for an indication of a presence of at least one defect on the railroad vehicle, wherein the at least one defect produces a periodic signal; and the computer system identifying the railroad vehicle as including a defect in response to identifying the indication of the defect on the railroad vehicle.