Between 11 September and 7 November, the attack cargo ship fitted out, conducted shakedown training, and underwent post-shakedown availability.

She completed repairs on 12 January 1945 and resumed amphibious training with other ships of Transport Squadron (TransRon) 16 at Maui and Kahoolawe Islands.

The attack cargo ship participated in the D-Day landings sending supplies and ammunition ashore to the troops struggling to wrest the island from a tenacious foe.

She arrived at Espiritu Santo on 19 March and began loading cargo the next day for the Army's 27th Division in preparation for the Ryukyus campaign.

She remained at Subic Bay until 25 June when she put to sea to participate in a month of amphibious exercises at Cebu with units of the Americal Division.

Whiteside returned to Subic Bay on 16 August and remained there until the 20th when she moved to Batangas on Luzon to load elements of the 1st Cavalry Division for occupation duty in Japan.

Whiteside arrived at Leyte on 11 September, fueled and provisioned, and then headed for Mindanao to load troops and cargo of the Army's 41st Infantry Division.

She remained in Japan until 15 October at which time she got underway for Manila in the Philippines to load landing craft for duty in conjunction with the transfer of Nationalist Chinese troops.

On the 26th, she arrived in Hai Phong, French Indochina, and began loading troops and cargo of the 583rd Regiment of the Nationalist Chinese Army.

On 5 June, she got underway for the Marshall Islands to provide support services for "Operation Crossroads", the large-scale nuclear tests conducted at Bikini Atoll that summer.

She reached Kwajalein Atoll on 17 June and remained in the Marshalls assisting the operation until the end of August when she embarked upon a voyage that took her to Okinawa, Guam, Eniwetok, and thence back to Pearl Harbor.

She arrived at Majuro on 30 November, visited Kwajalein during the first week in December, and Eniwetok in mid-month, before beginning a voyage that took her via Guam and Japan to China.

Whiteside arrived in San Francisco on 29 October to begin a seven-month tour of duty plying the waters along the west coast of North America.

She visited ports ranging south to San Diego and north to Adak and Kodiak in Alaska, though for the most part she remained in Californian waters.

Early in September, she stopped at Subic Bay in the Philippines before continuing on to the Marianas where she made port calls at Guam and Saipan.

Following a seven-day stop at Oahu, the attack cargo ship continued her voyage east on 7 October and arrived in Oakland, California, on the 12th.

In late August and early September, she made a round-trip voyage from the west coast to Pearl Harbor and back before entering the Mare Island Naval Shipyard for a three-month overhaul.

With elements of the 1st Provisional Marine Brigade (Reinforced) embarked, Whiteside stood out of San Diego on 14 July, bound for Japan.

The attack cargo ship arrived at San Francisco on 8 October and remained there for three weeks before getting underway to return to the Far East.

After a 10-day stay at Yokosuka and a brief stop at Sasebo, Whiteside arrived at Inchon on 10 December to participate in the evacuation of United Nations forces on the heels of the massive communist Chinese intervention.

She completed her last round-trip to the Orient on 28 February 1957 and, after almost a year of west coast operations, was decommissioned at Astoria, Oregon, on 30 January 1958.