Following an overhaul at San Francisco, California, Tautog resumed operations from Pearl Harbor in October 1943, sinking the Japanese submarine chaser No.

Assigned to training duty in February 1945, Tautog spent the rest of World War II in that role and supporting developmental work off Hawaii and the West Coast.

In 1947 Tautog went to the Great Lakes, where she was employed as a stationary Naval Reserve training submarine at Milwaukee, Wisconsin, for nearly twelve years.

[8] Following a short training period in Long Island Sound, Tautog departed for the Caribbean Sea on her shakedown cruise which lasted from 6 September 1940 to 11 November 1940.

After calls at Coco Solo, in the Panama Canal Zone, and San Diego, California, they arrived at Pearl Harbor on 6 June 1941.

On 21 October, she and USS Thresher stood out to sea, under sealed orders, to begin a 45-day, full-time, simulated war patrol in the area around Midway Island.

Shortly after the attack began on Ford Island, Tautog's gun crews, with the help of Narwhal and a destroyer, shot down a Japanese torpedo bomber as it came over Merry Point.

Around 10:00 on 26 April near Johnston Island, while en route to her station, Tautog sighted the periscope of an enemy submarine, apparently maneuvering to reach a favorable firing position.

Tautog made a sharp turn and fired one stern torpedo, evidently exploding above the target,[9] and was officially credited as sinking Ro-30 (1,047 tons).

[15] Her third war patrol, conducted from 17 July to 10 September 1942, took Tautog to the coast of Indochina, where (in part due to torpedo shortages) she laid mines.

Tautog prepared for battle, surfaced, closed the range, and fired a shot from her deck gun across the schooner's bow; the target hove to.

That night, Tautog was headed for Alors Strait when she sighted a ship (thought to be a freighter) coming west, accompanied by an escort.

[20] Later in the patrol, in the Salajar Strait, Tautog spotted a second cruiser (again thanks to ULTRA), and launched four torpedoes in heavy seas; all missed.

[25] During this patrol, in four battle surfaces to test her new gun (only the third 5"/25 cal pirated from an old V-boat,[25]) Tautog also sank a schooner, a sailboat, and a motor sampan.

With all torpedoes expended, Tautog tracked a convoy for two days while radioing its position back to Pearl Harbor before she returned to Midway Island on 18 November.

Tautog's ninth war patrol began on 12 December 1943 and took her to Japanese home waters, southeast of Shikoku Island and along the southern coast of Honshū.

On 3 January 1944, Tautog tracked a cargo ship off the mouth of the Kumano Kawa River, approximately one-half mile from the seawall.

The submarine ran up her periscope, but an explosion filled the air with debris and obscured Saishu Maru from view as the freighter sank.

While several members of her crew were doing emergency work on deck, a giant wave knocked them all off their feet and swept one man, newly assigned Motor Machinist's Mate R. A. Laramee, overboard; a search for him proved fruitless.

[30] On 13 March, Tautog tracked a freighter until she reached a good position for an attack and then launched three torpedoes from 1,500 yards (1,400 m), of which two hit and stopped Ryua Maru.

[25] Leaving the bait sitting, Tautog dived and began a submerged approach, firing a spread of three torpedoes; cargo ship Shojen Maru sank, more quickly than her inexplicably durable sister.

The next morning, Tautog made radar contact in a heavy fog, closing the enemy ship and firing four torpedoes; two hit the target.

[31] Three days later, the submarine fired her last three torpedoes[31] at Banei Maru Number 2 (1,100 tons)[31] and watched her disappear in a cloud of smoke.

A lone survivor, taken on board the submarine, identified the ship as Matsu Maru which was transporting a load of lumber from Tokyo to Muroran.

She then rescued six survivors from a swamped lifeboat who identified their ship as the Hokoriu Maru, en route from the Bonin Islands to Tokyo laden with coconut oil.

Tautog arrived there on 10 August, credited with a disappointing two ships for 4,300 tons (postwar reduced to 2,800);[35] she was routed to the United States for overhaul.

The submarine approached the wreckage and rescued one survivor who identified the ship as the motor torpedo boat tender Shuri Maru (1,800 tons),[37] en route from Tsingtao to Sasebo.

On 2 March, the submarine shifted her operations to Pearl Harbor to assist aircraft in anti-submarine warfare for one month before heading for the United States.

She reached San Diego on 9 April and operated in conjunction with the University of California's Department of War Research in experimenting with new equipment which it had developed to improve submarine safety.

Plans to use Tautog as a target during atomic bomb tests at Bikini Atoll in 1946 were cancelled, and she was assigned to the Ninth Naval District on 9 May 1947 as a reserve training ship.