Abstract: A linear vibration damping system includes a piston slideably disposed within a cylinder, a magneto-rheological fluid disposed within the cylinder, and a magnet disposed in magnetic communication with the magneto-rheological fluid. A rotary vibration damping system includes a cylinder having a steering shaft extending therethrough, a magneto-rheological fluid disposed between an inner surface of the cylinder and an outer surface of the steering shaft, and a magnet disposed in magnetic communication with the magneto-rheological fluid. In either system, the magnet is controllable to provide variable control of the magneto-rheological fluid. A method of damping vibrations in a motor vehicle includes disposing a magneto-rheological fluid at a source of vibration in the motor vehicle, controlling the magneto-rheological fluid to effectuate a structural change in the magneto-rheological fluid, and subjecting the magneto-rheological fluid to a vibration from the source of the vibration.