All "Leahy"-class ships were modernized again in the late 1980s New Threat Upgrade program. This program added advanced air search and track radars (AN/SPS-49 and AN/SPS-48E), updated targeting radars (AN/SPG-55), and combat direction systems. The upgrade included massive remodeling of the ship from food service space rehabilitation to a main propulsion system overhaul. Entire systems were removed and replaced, for example the AN/SPS-40 air-search radar was replaced with the AN/SPS-49 air-search radar. The upgrade was also quite expensive and the ships didn't serve much longer after the modification. For example, USS "Gridley" (CG-21) received NTU in 1991 at a cost of $55 million, but was decommissioned in early 1994.