The Series 72 had the same general appearance as the Series 75 but it was three inches shorter and set apart by rectangular taillights set high on the sides of the trunk. Recirculating ball steering was tried on Series 72 in 1940, to be adopted on all series in 1941. Like the Series 75 it was Fleetwood bodied, but rode on a 138 in (3,500 mm) wheelbase.
Source: wikipedia.org