Kraken steamed by way of Chicago to Lockport, Ill., 27 September 1944, and was carried in a floating drydock down the Mississippi River arriving at Algiers, La., 4 October.

Kraken departed on her second war patrol 15 March and maintained lifeguard duty in the South China Sea supporting aircraft carrier strikes against Singapore and Saigon.

Three days later, while chasing an eight-ship convoy, Kraken's torpedoes sank an oiler and a coastal steamer and her guns inflicted heavy damage on one of the Japanese submarine chasers.

While seeking the enemy in the Java Sea, her patrol was cut short when she received news of Japan's capitulation.

Kraken cleared Subic Bay 31 August 1945, touched at Pearl Harbor, and arrived at San Francisco 22 September.

Kraken remained in reserve status until 18 September 1958, when she was assigned to Pearl Harbor Naval Shipyard for activation overhaul and given a Fleet Snorkel conversion preparatory to transfer on loan to Spain.

She was to have been cannibalized, but had to be overhauled and recommissioned, 1 September 1975, to replace Narcíso Monturiol (S33), which had suffered a severe engine failure the previous spring and had to be stricken.