 On 1 May 1966, "Rockaway" again was reclassified, this time as a high endurance cutter, and was redesignated WHEC-377.On 26 September 1966 her period on loan to the Coast Guard ended when she was stricken from the Naval Vessel Register and transferred permanently to the Coast Guard.From 20 January 1967 to 30 March 1967, "Rockaway" conducted an "Eastern Tropical Pacific Cruise" in the Pacific off Mexico, where she undertook an oceanographic survey.