A tractor unit is a motor vehicle prepared to transport a towed or trailered load. Tractor units are generally used to pull semi-trailers, supported at the rear by their wheels and in the front by a fifth wheel attached to the hauling transport. A tractor unit hauling two or more semi-trailers or trailers is called a road train. Moreover, tractor units can carry the same modular shipping containers as freight ships and trains, and these vehicles are a versatile component of the global shipping industry.
Structure-wise, a tractor unit consists of the driver’s cabin, the motor, the chassis with several axles, and the coupling.
American tractor units have an engine and hood over the front axle in front of the cabin. European manufacturers produce cab over cabins - with a motor located below, under the driver.
Some tractor unit cabins also come equipped with sleeper compartments to accommodate those traveling overnight.
Most tractor units are equipped with diesel engines with large displacements and provide sufficient torque to haul heavy loads.
A tractor unit can have the number of axles depending on the axle load legislation of the country. A 6×4 axle configuration is most prevalent when delivering goods over long distances in large countries such as the USA and Australia. In Europe, the most commonly used options are 4x2 and 6x2.
A fifth wheel coupling is a mechanical lock system. The tractor truck’s fifth wheels are universal and standardized. And it is possible to attach to the vehicle any semi-trailer produced by different manufacturers.
At Truck1, a classified ad website, you will discover new and used tractor units suitable for various operations and industry sectors, including general haulage, waste management, construction, agriculture, mining, and more. Our extensive stock of tractor units for sale includes examples from such European brands as DAF, MAN, Mercedes-Benz, Scania, Volvo, and other makes. Browsing through our stock, you will be sure to find the tractor unit to suit your exact requirements and get a great deal.