Kenworth aerodynamic hood without sleeper
Mack hooded truck with sleeper
The cabin of a truck, often simply called a cab, is an enclosed space in a truck where the driver is seated. Some may refer to the tractor unit of a semi-trailer truck as a cab, but this is not the subject of this article. A sleeper is a compartment attached to the cab where the driver can rest while not driving, sometimes seen in semi-trailer trucks. They can range from a simple 2 to 4 foot (0.6 to 1.2 m) bunk to a 12 foot (3.7 m) apartment-on-wheels. Modern cabs usually feature air conditioning, a good sound system, and ergonomic seats (often air-suspended). There are a few possible cab configurations:
- Cab over engine (COE) or flat nose, where the driver is seated on top of the front axle and the engine. The front doors are typically in front of and above the front tires. This design is almost ubiquitous in Europe, where overall truck lengths are strictly regulated. They were common in the United States, but lost prominence when permitted length was extended in the early 1980s. To access the engine, the whole cab tilts forward, earning this design the name of tilt-cab. This type of cab is especially suited to the delivery conditions in Europe where many roads follow the layout of much more ancient path and trackways which require the additional turning capability of the cab over engine type. The operating conditions of these vehicles tend to be cooler than the conventional cab design and so the decreased engine suface area used for cooling in hotter climates is not required.
- Conventional cabs are the most common in North America. The driver is seated behind the engine, as in most passenger cars or pickup trucks. Conventionals are further divided into large car and aerodynamic designs. A "large car" or "long nose" is a conventional truck with a long (6 to 8 foot (1.8 to 2.4 m) or more) hood. With their very square shapes, these trucks experience a lot of wind resistance and typically consume more fuel. They also provide somewhat poorer visibility than their aerodynamic or COE counterparts. By contrast, Aerodynamic cabs are very streamlined, with a sloped hood and other features to lower drag. Most owner-operators prefer the square-hooded conventionals. The front doors are in back of (and mostly above) the front tires.
- Cab beside engine designs also exist, but are rather rare.
- Slang terms
