Submarine Boat Corporation, Newark, New Jersey, had operated the Newark yard to build Emergency Fleet Corporation (EFC) Design 1023 ships designed by Theodore E. Ferris for the United States Shipping Board (USSB) with thirty-two hulls cancelled as the war ended.^[2] After the war the USSB agreed to sell the yard to the operator after paying rent for three years and selling steel on hand at half the original cost.^[3] Those thirty-two ships were then completed on Submarine Boat's own account. Suwordenco, yard number 142, was launched on 22 October 1920 and completed in November 1920.^[4][2] The name was a construct given to all thirty-two ships. It was formed by a standard prefix "Su" and suffix "co" from Submarine Boat Corporation with an intervening "word" based on a person, place or company. Suwordenco was named for company general manager B. L. Worden.^[4][5] The ship, assigned official number 220862 and call letters MCBK, was registered in New York, New York operated by Submarine Boat's shipping subsidiary, Transmarine.^[2][5][6]

The standard ship's specifications were for a 3,545 GRT, 5,350 DWT ship of 335 ft 6 in (102.3 m) length overall, 334 ft (101.8 m) length between perpendiculars, 46 ft (14.0 m) molded beam, 28 ft 6 in (8.7 m) molded depth, loaded displacement of 7,615 tons with a draft of 23 ft (7.0 m). Ship's power for propulsion and auxiliaries was steam from two Babcock & Wilcox oil fired water tube boilers. Propulsion was by a Westinghouse steam turbine providing 1,500 shaft horsepower that could propel the ship at 10.5 kn (12.1 mph; 19.4 km/h). Five cargo holds had a bale capacity of 226,150 cubic feet (6,403.9 m³), and a grain capacity of 269,600 cubic feet (7,634.2 m³). Bunker capacity of 301,970 US gallons (1,143,100 L) gave a range of over 18,000 nmi (21,000 mi; 33,000 km).^[7]

Submarine Boat went into receivership in 1930 with its Transmarine operating subsidiary ceasing operations. Suwordenco, the last operating ship, arrived in the port of San Pedro, California on 13 January 1930 with an uncertain future.^[8] Suwordenco was sold later in 1930 to operate with the Admiral Line of the Pacific Steamship Company and renamed Admiral Halstead.^{[note 1][2][9][10]} After renovation by the Moore Dry Dock Company, Oakland, California, the ship was put on the Puget Sound — California route.^[11] In 1936 the ship was sold to Pacific Lighterage.^[2]

The company's main routes were from Alaska to California but it had some service into the Pacific to the Philippines. Admiral Halstead was on such service in May 1939 when it lent assistance to the effort to get the USS U. S. Grant off a reef at Guam.^[12]

Pacific Lighterage's Admiral Halstead entered the war as part of the Pensacola Convoy that departed Honolulu on the way to the Philippines. The ship's cargo was approximately 3,000 drums of aviation gasoline.^{[13][14][note 2]} The convoy, avoiding the Japanese Mandate island areas with a route southwest, had crossed the Equator on 6 December and received the news of war the morning of 7 December 1941. The convoy arrived at Brisbane on 22 December.^[14][15] On arrival Admiral Halstead was placed under U.S. Army charter with Pacific Lighterage as operator.^[16] The ship became part of the Southwest Pacific Area (SWPA) Australian based permanent local fleet on 31 December 1941 assigned the local identification number X-3.^[17]

The ship arrived in Darwin on 18 February 1942 loaded with 14,000 drums of aviation gasoline destined for the Philippines.^[18][19] On 19 February 1942 Japanese aircraft attacked the port, surrounding installations, and other ships in the port and area. Those ships included ships of the Timor convoy^{[note 3]} that had been escorted by USS Houston and turned back by air attacks. Admiral Halstead was strafed and near bomb misses sprung plates causing some flooding.^[19][20] The crew abandoned ship but returned to bring the ship in to unload the critical aviation gasoline cargo over a number of nights and going offshore to during the day.^[21] The crew of the heavily damaged and beached Portmar was drafted to unload the cargo. At one point, after objecting that the troops and Australian stevedores were idle and not so engaged, they were held under arrest.^[22]

Admiral Halstead remained with the SWPA permanent local fleet until August 1945.^[17]

Admiral Halstead was delivered for commercial operation to Pacific Lighterage at San Francisco on 2 March 1946.^[16] The company became Pacific Mail Steamship Company in 1947 with the ship operating with that line until broken up in 1949.^[2]

• SS Mopang sister ship
• SS Coast Farmer sister ship
• SS Coast Trader sister ship