Another major restyle arrived for the 25th-anniversary 1939 models, which Dodge dubbed the Luxury Liner series. These were once again completely redesigned, with new bodies for 1940, again in 1941, and a refreshing for 1942. However, just after the 1942 models were introduced, Japan's attack on Pearl Harbor forced the shutdown of Dodge's passenger car assembly lines in favor of war production in February 1942. 1941 saw the introduction of Fluid Drive for Dodge cars, which eliminated stalling or bucking if the clutch were released too quickly. This feature put a fluid coupling in between the engine and the clutch, although the driver still had to shift gears manually.