Abstract: A system for flushing ash from a diesel particulate filter includes a conduit for supplying a fluid from a fluid supply to an outlet of a diesel particulate filter. A pump slowly reverse flows the fluid through the diesel particulate filter. An acoustic wave source generates an acoustic wave, such as an ultrasonic wave, through the fluid in the diesel particulate filter to assist in dislodging the ash from the diesel particulate filter, while the fluid carries the ash out the inlet of the diesel particulate filter. The ash may be filtered from the fluid after the fluid exits the diesel particulate filter, so that the fluid may be reused.