A hydraulic vibration generation device or hydraulic motor is provided. The device includes a manifold having an inner volume with a pressure chamber formed in the inner volume, a fluid inlet orifice and a fluid outlet orifice. The device further includes a vibration generating member having a grooved drive and an off-center weight and retaining plates. The inner volume receives the vibration generating member within it. The vibration generating member rotates and generates vibration in response to hydraulic fluid flowing into the manifold through the inlet orifice and directed through the pressure chamber, relieves pressure upon exiting the pressure chamber into a pressure relief channel and out of the manifold through the outlet orifice. Also provided a hydraulic motor with a same manifold and pressure chamber, but with a power generating member having the same groove drive without an off-center weight. Rotation of the power generating member generates power.