Abstract: A drum dumper attachment for fork lift trucks carries its own power plant eliminating all heretofore required hose and other connections to the truck and controlled from the truck operator's seat by a demountable switch connected to the power plant through a single extension cord. The dumper attachment has hollow shoes receiving the truck forks, a rotatable clamp receiving a drum, a hydraulic jack rotating the clamp, an electric motor driven hydraulic pump for the jack, a battery energizing the motor, an electrically controlled valve selectively flowing fluid to and from opposite ends of the jack, and a double pole switch positionable adjacent the operator to energize the motor and the valve for causing the jack to rotate the clamp in opposite directions. The switch may be anchored to the truck by a magnet and the extension cord may be coiled to accommodate positioning of the switch.