The Hendrickson HAS Series single axle air suspension is made up of two air springs (7). The air springs are supported on main support beams (8), which are fastened to the axle and to the frame. A torque rod (14) from the frame bracket to the spring seat (11) or bottom axle cap (10) provides stability. Additional stability is provided by a transverse torque rod (20) from the frame to the axle housing. The shock absorbers (4) help to control jounce and rebound during vehicle operation.