Following the T-28's withdrawal from U.S. military service, a number were remanufactured by Hamilton Aircraft into two versions called the Nomair.

Later, a more ambitious conversion was undertaken as the T-28R-2, which transformed the two-seat tandem aircraft into a five-seat cabin monoplane for general aviation use.

The last T-28 in the Training Command, BuNo 137796, departed for Naval District Washington on 14 March 1984, in order to be displayed permanently at Naval Support Facility Anacostia, D.C.[4] In 1963, a Royal Lao Air Force T-28 piloted by Lieutenant Chert Saibory, a Thai national, defected to North Vietnam.

[10] On the night of 21 January 1971, PAVN sappers managed to get close enough to destroy the majority at Pochentong airbase.

So Petra, a common-law husband of one of the daughters of the overthrown Prince Norodom Sihanouk, machine gunned and bombed the palace of Lon Nol in an attempt to assassinate him, killing at least 20 and wounding 35, before defecting to Khmer Rouge held lands.

[11] France's Armée de l'Air used locally re-manufactured Trojans, T-28S Fennec, for close support missions in Algeria.

[citation needed] AeroVironment modified and armored a T-28A to fly weather research for South Dakota School of Mines & Technology, funded by the National Science Foundation, and operated in this capacity from 1969 to 2005.

[15][16] SDSM&T was planning to replace it with another modified, but more modern, former military aircraft, specifically a Fairchild Republic A-10 Thunderbolt II.

In addition, a considerable number of flyable examples exist in private ownership, as the aircraft is a popular sport plane and warbird.