2-6-6T

{{More citations needed|date=September 2023}}{{Short description|Locomotive wheel arrangement}}

Image:Alco 2-6-6 NYC.jpg-built 2-6-6 suburban tank locomotive of the New York Central and Hudson River Railroad.]]

In the Whyte notation for describing steam locomotive wheel arrangement, a 2-6-6 is a locomotive with a two-wheeled leading truck, six driving wheels, and a six-wheeled trailing truck. All the locomotives produced of this arrangement have been tank locomotives, and the vast majority in the United States. It was a popular arrangement for the larger Mason Bogies, as well as some of the largest suburban tank locomotives.

The locomotive was mostly used in the Denver, South Park and Pacific Railroad.{{Cite book |last=Robertson |first=Donald B. |url=https://books.google.com/books?id=-aWhRfr3rdkC |title=Encyclopedia of Western Railroad History |date=1986 |publisher=Caxton Press |isbn=978-0-87004-385-7 |page=37 |language=en}}{{Cite book |last=Poor |first=Meredith Clarence |url=https://books.google.com/books?id=aHLVAAAAMAAJ |title=Denver, South Park & Pacific: A History of the Denver, South Park & Pacific Railroad and Allied Narrow Gauge Lines of the Colorado & Southern Railway Company |date=1949 |publisher=Rocky Mountain Railroad Club |page=466 |language=en}} It also saw usage in New York and Chicago.{{Cite book |last=Kalmbach Media Company |url=http://archive.org/details/2022-03-01-classic-trains |title=Classic Trains - Spring 2022 |date=2022 |pages=18–21}}