The main characters are assigned to crew an M26 Pershing tank armed with a 90 millimeter gun, with which they breach the Siegfried Line in Germany sometime in the Fall of 1944.
In actuality, the M26 Pershing did not become operational until February 1945.
Furthermore, the actual tank used in the movie was an M46 Patton, a post-World War II upgrade of the M26 which did not enter service until 1949.
