They were built with the primary purpose of hauling long, heavy, high-speed express passenger trains for the C&O Railway such as the George Washington and the Fast Flying Virginian.

The first batch consisted of five "Greenbriers" (600-604) built in 1935 and named Virginia statesmen Thomas Jefferson, Patrick Henry, Benjamin Harrison, James Madison and Edmund Randolph.

The 1935 J-3s were the only "Greenbriers" built with Walschaerts valve gear, which was later changed to Baker, and were equipped with feedwater heaters and thermic siphons, arch tubes, and a combustion chamber in the firebox.

Timken roller bearings were used on the axles and running gear to reduce maintenance, and a different model of feedwater heater was fitted.

[4] Despite having a smaller heating surface than the earlier J-3s, the J-3as had firebox circulators, a larger combustion chamber, and larger-diameter flues in the boiler to improving steaming capacity.

[7] Today, 614 is on display at the C&O Railway Heritage Center in Clifton Forge, Virginia in the Greenbrier Presidential Express scheme, a luxury passenger train which never came to be.

On November 8, 2024, it was announced that C&O 614 was sold by Ross Rowland to RJD America, LLC of Denville, New Jersey, who will be restoring it to operating condition.