Cachalot was launched on 19 October 1933 as U.S.S. V-8 at Portsmouth Navy Yard. She was sponsored by Miss K.D. Kempff, and placed in commission on 1 December 1933 by Lieutenant Commander M. Comstock.
Following shakedown, tests, and overhaul, Cachalot sailed for San Diego, joining the fleet there on 17 October 1934. Through 1937 she operated mainly on the west coast. During this time she made two cruises to Hawaii, and one to the Panama Canal Zone.
On 16 June 1937, she departed San Diego for New London. While there, she participated in torpedo experiments at Newport, and in sound training exercises at the Submarine School. On 26 October 1937, Cachalot entered the New York Navy Yard for an extensive overhaul, remaining there for the next year.
On 16 June 1939, she reported to Pearl Harbor.
Cachalot was in the Pearl Harbor Navy Yard for overhaul during the Japanese surprise attack on 7 December 1941. The submarine suffered no damage, but one of her crew was wounded during the attack. Yard work was completed as quickly as possible, and Cachalot departed Pearl Harbor on her first war patrol on 12 January 1942.
Cachalot refueled at Midway, then conducted a reconnaissance of Wake, Eniwetok, Ponape, Truk, Namonuito, and the Hall Islands, returning to Pearl Harbor on 18 March 1942.
Following participation in the Battle of Midway, Cachalot departed on her second war patrol from Midway on 9 June 1942. Operating in Empire waters, Cachalot fired one torpedo for damage on a 9,200 ton tanker on 22 June. She returned to Pearl Harbor on 26 July.
Cachalot began her final war patrol on 23 September 1942, patrolling in the Bering Sea in support of operations in the Aleutian Islands.
Following her third war patrol, Cachalot was determined to be obsolete for offensive operations and returned to New London, where she served as a training submarine at the Submarine School until 30 June 1945. She then sailed to Philadelphia, where she was decommissioned on 17 October 1945. She was sold for scrap on 26 January 1947.
Cachalot was awarded three battle stars for her World War II service.
Sponsor: Miss K.D. Kempff
First Captain: LCDR M. Comstock
Stricken/Lost: Scrapped 1947