After repairs and training at Pearl Harbor, "Colahan" sailed on 31 May 1944 to rejoin the 5th Fleet, operated on radar picket, shore bombardment and fire support duty during the bombardment, capture, and occupation of Guam from 12 July to 15 August and screened air strikes in support of the invasion of the southern Palaus from 29 August to 28 September. "Colahan" screened the Fast Carrier Task Force (then 3rd Fleet's TF 38, later 5th Fleet's TF 58) as it prepared for the Leyte assault with air strikes on the Nansei Shoto and Formosa from 10–14 October, then began strikes in the Philippines until 20 October, day of the landings. Carriers she guarded struck the retiring Japanese forces after the Battle of Surigao Strait phase of the massive Battle for Leyte Gulf of 24–26 October. Continued air operations in the Philippines claimed her services until she put into Ulithi for repairs late in December after riding out "Halsey's Typhoon".