Post-World War II, "Caiman" operated out of San Diego, Guam, and Pearl Harbor in 1946. In 1947 she made an Arctic familiarization cruise out of Seattle as part of Operation Blue Nose. Thereafter, based on Seattle, she served as reserve training ship until 23 April 1951, when she began a GUPPY conversion at Mare Island Naval Shipyard. Since then based at Pearl Harbor and San Diego, "Caiman" has alternated local operations and fleet exercises with tours of duty in the Far East at 18-month intervals. On her 1957 cruise, Brisbane, Australia, was added to her more usual itinerary of Japanese and Philippine ports.