4-4-4T

Under the Whyte notation for the classification of steam locomotives, 4-4-4 represents the wheel arrangement of four leading wheels on two axles, four powered and coupled driving wheels on two axles, and four trailing wheels on two axles. In the United States, this arrangement was named the Reading type, since the Philadelphia and Reading Railroad was the first to use it. In Canada, this type is known as the Jubilee.

Other equivalent classifications are:

A single, experimental 4-4-4, classified as S 2/6, was built for the Royal Bavarian State Railway Company in 1906 by the firm of J.A. Maffei. It was successful in an experimental sense but was too light to haul passenger trains of useful capacity. It was fast, attaining 154 km/h (96 mph) on test, and was semi-streamlined with a pointed nosecone and fairings around the cylinders, stack and dome, and slanted-back cab windows. It inspired the later Bavarian S 3/6 4-6-2 "Pacifics". It passed to the Deutsche Reichseisenbahnen when the German railways were centralised, and was classified as BR 15, number 15 001. It was taken out of service in 1925, and was restored by Maffei to be exhibited at the Munich Transport Exhibition of that year. After the exhibition ended, it was placed in the Nuremberg Transport Museum, where it remains.

The Philadelphia and Reading Railway built four C1a Class locomotives in 1915. They proved to be quite unstable; after that year, they were rebuilt to 4-4-2 "Atlantic" locomotives. The Baltimore and Ohio Railroad created a single 4-4-4 in 1934, rebuilding a 4-4-2 "Atlantic" into a solitary class J-1, named Lady Baltimore. Along with the single class V-2 4-6-4 Lord Baltimore, it was built for new lightweight passenger trains, in the Lady Baltimore's case the Abraham Lincoln on the Chicago and Alton Railroad, a wholly owned subsidiary of the B&O. Despite the Alton's flat territory and straight track, the locomotive did not do well. It was returned to the B&O and was again modified at the railroad's Mount Clare shops, a less streamlined cab and front end being fitted. Subsequently, it was placed into local service on the railroad's Wheeling Division, mostly operating between Holloway and Cleveland, Ohio. It proved no more successful in that service, and was sent to the B&O's Riverside Shop for storage; it was scrapped in 1949.

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