The T54 was a series of prototype American tanks of the 1950s with three different turrets, all armed with a 105mm gun, mounted on the M48 Patton

M48 Patton

The M48 Patton is a medium tank that was designed in the United States. It was the third and final tank to be officially named after General George S. Patton, commander of the U.S. Third Army during World War II and one of the earliest American advocates for the use of tanks in battle It was a...

 chassis. The original T54 had a conventional turret with an autoloader, while the turret on T54E1 was of an oscillating design

Oscillating turret

An oscillating turret is a form of turret for armoured fighting vehicles, both tanks and armoured cars. The turret is unusual in being made of two hinged parts. Both elevation and recoil rely on the upper part of the turret moving relative to the lower part....

 with an autoloader

Autoloader

An autoloader or auto-loader is a mechanical aid or replacement for the personnel that load ordnance into crew-served weapons, such as tanks and artillery...

 and the one on T54E2 was conventional with a human loader. The turret on T54E1 was similar to that of the T69 in its oscillating design and in that it held a crew of three and a nine-round drum autoloader under the gun. The T54E1 was abandoned in 1956 and in 1957 the entire project was cancelled in favor of the T95

T95

The T95 was an American prototype medium tank developed from 1955 to 1959. These tanks used many advanced or unusual features, such as siliceous-cored armor, a new transmission, and the OPTAC fire-control system...

.