A hanger beam assembly (20) is formed from aluminium and includes first (26) and second (28) support brackets, a main beam hanger (30), a driver beam (22), a main beam (24), a main beam support (32), and a main beam support mounting bracket (34). The main beam support mounting bracket (34) has a first lateral end (34a) that is mechanically secured to the main beam support (32) and a second lateral end (34b) that is mechanically secured to a center support (36). A bottom wall (34m) of the main beam support mounting bracket (34) includes slotted mounting openings (32g) for receipt of fasteners for attachment to a floor tunnel (52b) of a vehicle floor and frame cross-member. The bottom wall includes first (34n), second (34o), and third (34p) planar surfaces that interact with first (52h), second (52i), and third (52j) surfaces of the floor tunnel in the vehicle. The resulting hanger beam assembly is light-weight and provides a desired natural frequency at the associated steering wheel.