Assigned to Caribbean shuttle runs after commissioning, Ramapo carried petroleum products from Port Arthur, Texas, to Guantanamo Bay and the Canal Zone until April 1920.

En route she performed collateral duties as a survey ship and collected data in central and western Pacific island groups for the Hydrographic Office.

On 7 February 1933, while cruising across the Pacific Ocean from Manila to San Diego, the ship encountered the tallest rogue wave ever recorded at the time, measuring 34 metres (112 ft) in height.

Arriving at Kodiak on 29 July 1942 on her first such run since 1937, she plied between Port Townsend and various mainland and Aleutian stations throughout World War II.

Wasmuth was escorting a convoy through a heavy Alaskan storm when two depth charges were wrenched from their tracks by the pounding sea, fell over the side, and exploded beneath the ship's fantail.