On 13 February 1969, "Theodore E. Chandler" completed a four-month overhaul at Long Beach and began 1st Fleet operations along the west coast. After seven months of exercises and training cruises, she departed the west coast on 24 September and headed back to the western Pacific. During that deployment, she spent most of her time at sea off the coast of Vietnam engaged in familiar duty as naval gunfire support ship, SAR picket, and as escort for aircraft carriers. In addition to stops at Sasebo, Yokosuka, and Kaohsiung, she made a port call at Bangkok, Thailand. On 17 March 1970, after six weeks in and out of Sasebo as escort to the carrier , the destroyer departed Japan to return to the United States. She reached Long Beach on 1 April and resumed operations with the 1st Fleet. That summer, she participated in an NROTC summer training cruise and then spent all of August and most of September in port at Long Beach. Late the following month, she began preparations to return to the western Pacific; and, on 13 November, the warship departed Long Beach.