North Atlantic Treaty Organization (NATO) exercises in the Irish Sea in September and October 1957 took her to Plymouth, England, and Brest and Cherbourg, France.

On 12 May 1958 Dealey sailed for the Mediterranean as flagship of Escort Squadron 10 (CortRon 10), screening the aircraft carrier USS Wasp to her duty with the United States Sixth Fleet.

On 3 February 1959 Dealey put to sea for Guantanamo Bay Naval Base, Cuba, and after exercises there transited the Panama Canal for calls at Buenaventura, Colombia; Salinas, Ecuador; Talara and Callao, Peru; and Valparaíso and Antofagasta, Chile.

She was transferred to the Uruguayan Navy the same day, and renamed ROU 18 De Julio (DE-3), the third ship to commemorate the date of the adoption of Uruguay's first constitution.

In 1981, 18 de Julio rescued the crew of the merchant ship MS Harp, sunk in heavy storm in the South Atlantic Ocean.