Abstract: A vibrating tool comprising a hammer and valve that oscillate axially inside a housing to produce vibrations solely in response to fluid flow through the tool at an operating flow rate. The valve is supported by a spring that resists compression until a minimum operating flow rate is achieved, and hammer is also spring-loaded. When the valve strokes down and engages the hammer, flow through the hammer is restricted. Increased fluid pressure pushes the hammer down away from the valve, resulting in a sudden decrease in pressure, allowing both the hammer and valve to rebound and create vibrational impacts. The cycle repeats continuously as long as an adequate flow rate is maintained.