A frame assembly for an off-road vehicle including a left frame rail and a right frame rail that are identical to each other, a front frame module that includes at least one left toot and at least one right foot, an occupant frame module that includes at least one left foot and at least one right foot, a rear frame module that includes at least one left foot and at least one right foot, and a plurality of identical adapters mounting the components to the left and right frame rails.