Terminal tractor
truck that moves semi trailers within a cargo yard
A terminal tractor, known in the United States as a shag truck, shunt truck, spotter truck, spotting tractor, yard truck, yard shifter, yard dog, yard goat, yard horse, yard mule, yard hostler, yard spotter, hostler, or mule, is a kind of semi-tractor intended to move semi-trailers within a cargo yard, warehouse facility, or intermodal facility, much like a switcher locomotive is used to position railcars. In the United Kingdom they are known as terminal lorries or terminal trucks. In the United States the term is most often called a yard driver or switcher, often given the nickname yard dog, affectionately not derogatively. Yard dogs are generally thought well of by other drivers because they will often back trailers into docks that are narrow or difficult to pull off by large OTR tractors with sleeper berths.
Some manufacturers include Terberg from The Netherlands and Kalmar Ottawa from the U.S.
Characteristics
Distinctions between a terminal tractor and a regular tractor unit include:
A single-person cab offset to the side of the engine.
A full-height, sliding rear door for easy access to trailer connections.
A very short wheelbase, usually with a solidly mounted rear axle.
A low-power diesel, alternative fuel engine, or electric motor usually with an automatic transmission.
A fifth-wheel coupling with an integrated lifting mechanism allows the semi-trailer's legs to remain in the lowered position during movement. 380 millimetres (15 in) and 32,000 kg (71,000 lb) of hydraulic lift is typical.
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This entry incorporates text from “Terminal tractor” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.