Abstract: A hydraulic retarder and control composed of an accumulator, for rapid filling of the retarder; a pulse valve, for controlling fluid flow to and from the accumulator; a regulator valve, for limiting the inlet pressure to the retarder; and a pair of check valves, for preventing fluid flow from the retarder to a pressure source and from the retarder to the accumulator. The pulse valve is controllable to provide rapid filling of the retarder, while the regulator valve will direct fluid from a secondary source to the retarder and control the pressure at the retarder inlet. The accumulator is filled from the main pressure source, between retard requests, at a rate that does not disturb the main transmission pressure level. One of the check valves and the pulse valve prevent the fluid in the accumulator from returning to the system other than when a retard request is present.