Bogies

A bogie (/ˈboʊɡi/ BOH-ghee) (in some senses called a truck in North American English) is a chassis or framework carrying wheels, attached to a vehicle, thus serving as a modular subassembly of wheels and axles. Bogies take various forms in various modes of transport. A bogie may remain normally attached (as on a railway carriage [car] or locomotive, or on a semi-trailer) or be quickly detachable (as the dolly in a road train); it may contain a suspension within it (as most rail and trucking bogies do), or be solid and in turn be suspended (as most bogies of tracked vehicles are); it may be mounted on a swivel, as traditionally on a railway carriage or locomotive, additionally jointed and sprung (as in the landing gear of an airliner), or held in place by other means (centreless bogies).

While bogie is the preferred spelling and first-listed variant in various dictionaries,bogey and bogy are also used.

A bogie in the UK, or a railroad truck, wheel truck, or simply truck in North America, is a structure underneath a train to which axles (and, hence, wheels) are attached through bearings. In Indian English, bogie may also refer to an entire railway carriage.

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