2-8-8-8-2

Under the Whyte notation for the classification of steam locomotives, a 2-8-8-8-2 has two leading wheels, three sets of eight driving wheels, and two trailing wheels. Because of its length, such a locomotive must be an articulated locomotive. It is not longer than a normal articulated; the third set of drivers is located under the tender. All of the examples produced were a Triplex of the Mallet type.

Other equivalent classifications are:

Baldwin built the only three examples of the type for the Erie Railroad between 1914 and 1916. The first was named Matt H. Shay, after a beloved employee of that road. It could pull 650 freight cars. All three, as well as the lone 2-8-8-8-4 and several Virginian Railway electrics, shared the nickname "Triplex" because of their three sets of drivers. (Compare Duplexes, which had two sets.)

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