Embodiments provide an aerodynamic fairing system that may comprise a base configured to mount to a vehicle, an arm coupled to the base at a proximate end and extending laterally, and a fairing mounted to the arm having an inboard and an outboard surface. The fairing outboard surface may provide an aerodynamic outer surface to direct flow to an angle to the rear. The arm may a fixed or adjustable length arm. The arm may provide a mounting area for a mud flap such that aerodynamic system may act as a mud flap hanger. Embodiments also provide an adjustable mud flap hanger.