Abstract: A spreader assembly for spreading a material and for mounting to a bed of a truck is disclosed. The assembly includes a hopper and a frame having an upper rail for supporting the hopper in the bed of the truck. The frame includes a pair of front and rear posts extending downwardly from the upper rail and an upper rail extending in a cantilevered fashion from the rear posts to support the outlet spout outside the bed of the truck. A quick-release connector releasably engages the frame for preventing longitudinal movement within the bed of the truck. A spinner is rotatably attached and is moveable between an operating position and a storage position. The hopper includes a lower portion having a bottom with a first slanted portion having a first slope and a second slanted portion having a second slope with the first slope being different than the second slope.