Steam Locomotive No. 4039 was built November 1942 for the U.S. War Department by the American Locomotive Company (ALCO) of Schenectady, NY (ALCO Construction No. 70421; Corps of Engineers Spec. No. T-1560; Purchase Order No. DA1873). Eighty (Nos. 4000-4079) nearly identical "060-155"-class locomotives were constructed. Their intended purpose was for U.S. military service in the Far East, Africa and Europe during World War II. However, upon delivery to the Army all of the engines were instead used to switch various stateside military bases throughout the duration of the war.

Excellent history and description of the ex-U.S. Army 0-6-0 No. 4039 now owned by the Whippany Railway Museum in New Jersey.