She struck a submerged object 3 February 1921 and was forced to enter dry dock in Pola, Italy (now Pula, Croatia) for repairs to her starboard propeller and shaft.

This varied duty was highlighted by a cruise to Nicaragua in 1926 to protect American lives and property during the guerrilla war led by Augusto César Sandino, an escort voyage to Havana guarding President Calvin Coolidge in Texas in 1928, and disaster relief work in the Caribbean during the same year.

[4] She conducted patrols and exercises in the Atlantic and Caribbean until reaching San Diego 4 November 1940 and continued these duties along the Pacific coast until the United States entered the war.

She sailed from Seattle 29 January via San Diego for Pearl Harbor, arriving 13 February, and subsequently escorted merchantmen to Espiritu Santo, where she moored 9 March and commenced amphibious training exercises with the 4th Marine Raiders Battalion.

Gilmer engaged in patrols of Buna, Cape Sudest, and Australia and bombarded Humboldt Bay, New Guinea, 22 April 1944 when Army forces began the assault.

Tinian Town was bombarded 23 June and UDT operations off that island continued until 14 July when Gilmer, along with William C. Miller, formed an offensive antisubmarine warfare group and sank I-55[6] in 18°18′N 146°26′E / 18.300°N 146.433°E / 18.300; 146.433 (Sinking of Japanese Submarine).

UDT teams were landed on the eastern and western beaches, and Gilmer screened Tennessee as the big ship bombarded Japanese defenses on Iwo Jima.

After further escort and patrol voyages along the China coast, Gilmer sailed from Qingdao 26 November for the United States and finally moored in the U.S. again at Philadelphia 11 January 1946.