The tug operated out of the Cuban base through 1923, making periodic voyages to Key West, Norfolk and ports in the Bahamas until sailing for Charleston, South Carolina, on 24 April 1923.

Arriving on 1 May, Montcalm was repaired and served locally and at Philadelphia before returning to Guantanamo Bay on 19 June 1924.

She operated on numerous voyages along the Gulf and east coasts, as far west as Galveston, Texas, and as far north as Norfolk.

During World War II she continued her vital services in the Gulf of Mexico and the Caribbean.

Following the end of the war, the tug decommissioned at Charleston Navy Yard on 24 May 1946, was struck from the Naval Vessel Register on 13 June 1946, and was sold to J. C. Berkwit & Co., New York City, on 12 February 1947.