Under restoration to service at the Whippany Railway Museum
United States Army Steam Locomotive No. 4039, is located in the Whippany section of Hanover Township, Morris County, New Jersey, United States. The locomotive was built in 1942 and added to the National Register of Historic Places on March 4, 2002. The locomotive is part of the Whippany Railway Museum.
The locomotive was built by the American Locomotive Company in November 1942 for the U.S. War Department. The locomotive is a 0-6-0 "Switching"-type built for Standard gauge track. The intended use of the locomotive was for U.S. military service in the Far East, Africa and Europe, but instead was used for switching operations for military bases within the United States during World War II. After WWII the locomotive was no longer needed by the War Department and was sold to the Virginia Blue Ridge Railway on February 17, 1947. The locomotive was used in freight operations until August 1, 1963 when it was taken out of service when the Virginia Blue Ridge Railway made the change over to diesel locomotives.
In 1965, the locomotive was sold to the Morris County Central Railroad and was used for passenger rail excursions. The locomotive's last run was on December 14, 1980 between Newfoundland and Stockholm, New Jersey. The Whippany Railway Museum acquired the locomotive on May 7, 1994 and cosmetically restored it for static display. The Morris County Board of Chosen Freeholders adopted a Resolution designating the locomotive "The Official Steam Locomotive of Morris County" on January 26, 1997.