 They were replaced by the Pullman reassigning existing cars – the second 400 was the former 1939 New York World's Fair exhibition car "American Milemaster", the replacement 401 was previously the experimental "Muskingum River".Both cars were rebuilt with flat-ended observation lounges in 1956.During World War II coaches were added to the train along with 500-series 6-section, 6-roomette, 4-double bedroom cars reassigned from Overland Route service to the "Oakland Lark".