The construction was financed by Maryland Steel with a credit plan that called for a 5% down payment in cash with nine monthly installments for the balance.

[4] She had a deadweight tonnage of 10,175 LT DWT,[2] and her cargo holds, which had a storage capacity of 492,255 cubic feet (13,939.1 m3),[2] were outfitted with a complete refrigeration plant so that she could carry perishable products from the West Coast—like fresh produce from Southern California farms—to the East Coast.

This loss of access coupled with the fact that the Panama Canal was not yet open, caused American-Hawaiian to return in late April to its historic route of sailing around South America via the Straits of Magellan.

[14] In October 1915, landslides closed the Panama Canal and all American-Hawaiian ships, including Panaman, returned to the Straits of Magellan route again.

She may also have been in the group of American-Hawaiian ships chartered for service to South America, delivering coal, gasoline, and steel in exchange for coffee, nitrates, cocoa, rubber, and manganese ore.[16] At some point after the United States declared war on Germany, the United States Army chartered Panaman for transporting pack animals to Europe in support of the American Expeditionary Force.

[17] Although there is no information about the specific conversion of Panaman, for other ships this typically meant that passenger accommodations had to be ripped out and replaced with ramps and stalls for the horses and mules carried.

On 12 August, Panaman was transferred to the United States Navy at New York, and was commissioned into the Naval Overseas Transportation Service (NOTS) the same day.

Panaman was loaded with a cargo of general supplies, beef, and a deck-load of trucks and sailed in a convoy from New York on 21 September, arriving at its destination of Saint-Nazaire 6 days later.

[5] Though sources do not indicate the specific modifications Panaman underwent, typical conversions for other ships included the installation of berths for troops, and adding greatly expanded cooking and toilet facilities to handle the large numbers of men aboard.

Though the company had abandoned its original Hawaiian sugar routes by this time,[22] Panaman continued inter-coastal service through the Panama Canal in a relatively uneventful career.

In April 1923, for example, the newspaper ran a report provided by the Los Angeles Chamber of Commerce that went into great detail listing the contents of the 2,651,042-pound (1,202,492 kg) cargo that Panaman had unloaded.

[23] In June 1926, the newspaper ran a photograph that showed the loading of a $1,000 prize bull that was beginning its journey from Los Angeles Harbor to Guatemala City aboard Panaman.

[25] But on arrival in Los Angeles Harbor, the ship was boarded by three FBI agents and two representatives of the Bureau of Marine Inspection and Navigation.

From August 1942 to April 1943, Panaman sailed primarily between New York and Caribbean ports, calling at Trinidad, Key West, Hampton Roads, and Guantánamo Bay.

[28] According to personal letters sent from the Philippines by a crewman to family members, "Panaman" served in the Pacific Theater in the summer of 1945.