Abstract: A removable knockdown truck rack having independent front and aft support frames. Each support frame having two spaced apart side-posts, each side-post being rigidly connected to a cross rail disposed therebetween thereby forming a moment resistant frame to resist lateral forces transverse to the truck. Each side-post of the frames being supported by a socket assembly adapted to be attached to the cargo bed of a truck. Each said socket assembly having a receiving socket disposed to securably receive a side-post therein. Wherein the receiving sockets are braced to resist longitudinal forces imparted substantially by acceleration and deceleration of the truck.