During World War II, it built submarines, tank landing craft (LCTs), and self-propelled fuel barges called "YOs".
The Navy paid for lift machinery on Chicago's Western Avenue railroad bridge to clear a submarine.
However, they were completed by Manitowoc as Gatos, due to an unavoidable delay in Electric Boat's development of Balao-class drawings.
Landing Craft Tank has a: displacement of 285 tons, length of 114' 2", beam of 32' 8", draft of 3' 6", top speed of 10 kts., a range of 700 nautical miles, held 1 officer and 10 enlisted men, a cargo capacity of 150 short tons, armament of two single 20mm AA guns, and two .50 cal.
Post World War 1 Manitowoc built: scows, tugboats, barges, a ferry, three patrol boats for the U.S. Coast Guard and the Presidential yacht USS Potomac (AG-25) (1934).
After World War 2 Manitowoc continued to build ships, barges and dredges, from 150 to 649 DWT, until the shipyard closed in 1972.
Notable post war ships: MV Saginaw (1953) and SS Edward L. Ryerson (1960).