 From 10 October to 19 November 1964, "Lloyd Thomas" escorted 28,000 Marines from Little Creek, Va. to the coast of Spain during "Operation Steel Pike I", the largest peacetime amphibious operation ever conducted.During 1965 the destroyer, after installing new electronic gear to update her antisubmarine capabilities, trained in Guantanamo Bay, then participated in the late summer antisubmarine operation, CANUS-SILEX, with the Royal Canadian Navy in the western Atlantic.On 15 February 1966 she deployed from Newport again to the Mediterranean.