"Jeffers" was converted to a destroyer-minesweeper at New York, and was reclassified DMS-27 on 15 November. She sailed 3 January 1945 for the Panama Canal and California, arriving San Diego for training on 17 January. In February she moved on to Pearl Harbor and from there to the great advance base at Ulithi to prepare for the Okinawa invasion, last and largest amphibious operation of the war against Japan. As part of the preliminary minesweeping group, "Jeffers" arrived off Okinawa on 24 March, one week before the landings, and began clearing mines and marking boat lanes. During the assault on 1 April the ship moved to antisubmarine screening and air defense. During the Japanese air attack of 6 April she downed a twin-engine bomber. Six days later, while on radar picket station, she again was under heavy air attack. She downed at least one of the attackers and was nearly hit by a Yokosuka MXY-7 Ohka as the attack was repulsed. "Jeffers" then assisted survivors of sunken .