A continuous, hydroformed tubular member includes a horizontal member having a first end and a second end. A first vertical member has a first lower end coupled to the first end of the horizontal member. The first vertical member also has a first upper pillar-free end to form a first pillar configured to form a terminal end of an upwardly-open rear bed of a motor vehicle. A second vertical member has a second lower end coupled to the second end of the horizontal member. The second vertical member also has a second upper pillar-free end to form a second pillar configured to form the terminal end of the upwardly-open rear bed of a motor vehicle. The horizontal member, the first vertical member, and the second vertical member together form a one-piece, unitary U-shaped member.