Abstract: A self-propelled concrete vibrator machine adapted for movement along a pair of spaced-apart guide rails which are positioned on the bridge centering upon which the concrete is to be poured. The concrete vibrator machine is adapted to be moved along the guide rails closely adjacent the forward end of a concrete finishing machine. The vibrator machine comprises first and second drive units mounted on the guide rails for selective movement on the guide rails in either forward or reverse directions. A truss assembly is secured to the rearward ends of the drive units and extends therebetween over the area upon which the concrete is being poured. A plurality of vertically disposed and horizontally spaced hydraulic vibrators are mounted on the rearward end of the truss assembly.