On 22 October 1943 Cacapon sailed from Norfolk, Virginia, to load fuel at Aruba in the West Indies en route to Pearl Harbor, where she arrived 12 November.

After a west coast overhaul, she returned to Pearl Harbor, from which she sailed 3 February 1944 to carry her vital logistic support to task force TF-50, then engaged in the Marshall Islands operation.

She carried fuel on which all modern naval warfare depends to units of the U.S. 3rd Fleet from March into May, as the mighty task forces sent their strikes against Rabaul, Kavieng, Green, Emirau, and the Admiralties.

Cacapon brought her essential aid to the 3rd Fleet in its final devastating air attacks and bombardments on the Japanese home islands in July 1945, and on 20 September entered Tokyo Bay.

Far Eastern operations continued to be the rule for Cacapon when war broke out in Korea in June 1950; she completed four lengthy tours of duty there during the three years of fighting.

On her first tour, during which she helped to support the amphibious landing at Inchon on 15 September 1950, she earned the Navy Unit Commendation for her high performance of duty.

In 1958 she served as the oiler replenishing the ships in Operation Hardtack, which conducted nuclear bomb tests in the lagoons of Bikini and Eniwetok, Marshall Islands.

[2] After a lengthy interrogation, LeBrun confessed to the murder and to disposing of the body by throwing Ensign Muns into one of the oiler's massive fuel tanks.