Susquehanna sailed for San Diego, California, on 25 June to begin her shakedown cruise which ended one month later. She moved up the coast to San Pedro, California, to load and, on 27 July, got underway for Australia. The tanker arrived at Townsville, Queensland, on 18 August and was attached to the Service Force, Seventh Fleet. On 4 September, she was underway for the Milne Bay area of New Guinea to service fleet units there. She returned to Australia to load cargo and aviation gas, from 23 November to 29 November, and delivered it to Milne Bay. Susquehanna operated between Australian and New Guinea ports until December 1944. She made two trips to the Netherlands East Indies and, in addition to supplying gas for large fleet units, serviced PT boats at Buna and other bases.