Built in 1953, by Levingston Shipyard of Orange, Texas (hull #506) as the Esso Tug No. 20 for Esso Shipping of Wilmington, Delaware.
In 1955, she was renamed as the Esso Massachusetts.
In 1973, the tug was acquired by Exxon Shipping of Linden, New Jersey where she was renamed as the Exxon Massachusetts.
In 1980, she was acquired by White Stack Towing and Transportation Company (a Turecamo Maritime subsidiary) where she was renamed as the Robert B. Turecamo.
In 1998, Turecamo Maritime was acquired by the Moran Towing Corporation where the tug retained her name.
Originally powered by a single 2tew 16cyl GM Cleveland diesel engine, rated at 1,600 horsepower. In 1990, the tug was repowered with a single 2tew 16cyl Alco diesel engine. She is a single screw tug rated at 3,000 horsepower.