DODX Guard Car No. G-56

The DODX Guard Car No. G-56 is a historic railroad car at the Arkansas Railroad Museum in Pine Bluff, Arkansas. It was built about 1942 by the American Car and Foundry Company, and is a rare surviving example of a World War II troop transport, and as a railroad guard car used by the United States Department of Defense in the management of hazardous and valuable cargos that it transported by rail. The car is silver, with a horizontal black stripe on the side.

The car was listed on the National Register of Historic Places in 2007.