A low profile chassis and suspension system for a road vehicle. The
chassis supports a payload section or cargo compartment, such as for a
delivery truck, ambulance, or shuttle bus. The chassis includes a largely
planar frame having a top surface which is located beneath the rotational
axes of the rear wheels. The wheel suspension system is particularly
compact and close to the road surface. In some embodiments each wheel is
suspended from the vehicle by a pair of pivotal support arms. Preferably,
one arm is located above the other arm, and both arms pivot along pivot
axes that are generally perpendicular to the rotational axis of the
supported wheel. A spring urges one of the arms apart from the frame. In
other embodiments, the spring is placed beneath the rotational axis of
the wheel. In some embodiments both of the pivoting support arms are
located beneath the rotational axis of the wheel.