Abstract: A tool box assembly for installation in pickup trucks is provided. A pair of tool boxes are pivotally mounted in an enclosed frame for movement between an access position and a secured position. The movement of the tool boxes is driven by a hydraulic system. In the access position, the tool boxes are supported in an open position above the sidewall of the truck. In the secured position, the tool boxes are enclosed completely by the frame which does not extend above the sidewalls of the truck. As the boxes are raised, the lids are opened. When the boxes are lowered, the lids are closed and locked in a closed position.