is an automobile built with a folding, retracting, or removable roof. The collapsible roof section is typically made from flexible canvas or vinyl, although plastic, aluminium and steel have occasionally been used in elaborate folding designs.
Unlike a roadster, which may also have a folding top, a convertible has roll-up glass windows in the sides, and so the entire vehicle is "convertible" to an enclosed coupé.
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A truck is a motor vehicle for transporting goods. Unlike automobiles, which usually have a unibody construction, most trucks (with the exception of the car-like minivan) are built around a strong frame called a chassis. They come in all sizes, from the automobile-sized pickup truck to towering off-road mining trucks or heavy highway semi-trailers.
The term is most commonly used in American English and Australian English to refer to what earlier was called a motor truck, and in British English is often called a lorry or, for bigger vehicles, a Heavy Goods Vehicle (HGV). This type of truck is a motor vehicle designed to carry goods, with a cab and a tray or compartment for carrying goods. In Australia and New Zealand a small truck with an open tray is called a "ute" (utility vehicle).
"Pantechnicon" is a British word for a furniture removal van that has now fallen out of usage. It was originally coined in 1830 as the name of a craft shop or bazaar, in Motcomb Street in Belgravia, London. The shop soon closed down and the building was turned into a furniture warehouse, but the name was kept. Vehicles transporting furniture to and from the building, known as pantechnicon vans, soon came to be known simply as pantechnicons. A Pantech truck or van is a word derivation of pantechnicon commonly and currently used in Australia. Pantech refers to a truck and/or van with a freight hull made of (or converted to) hard panels (ie. chilled freight, removal vans etc).
Types of trucks by size
Light trucks
Light trucks are car-sized (in the US, no more than 6,300 kg (13,000 lb)) and are used by individuals and commercial entities alike. They are comprised of:
- Pickup trucks
- Full-Size vans
- Minivans
- SUVs
Medium trucks
Medium (or medium-duty) trucks are bigger than light but smaller than heavy trucks. In the US, they are defined as weighing between 6,300 kg (13,000 lb) and 15,000 kg (33,000 lb). For the UK the cut-off is 7.5 tonnes. Local delivery and public service (dump trucks, garbage trucks) are normally around this size.
Heavy trucks
Three Road Trains, Western Australia Heavy trucks are the largest trucks allowed on the road. They are mostly used for long-haul purposes, often in semi-trailer configuration. In Australia many trailers are connected to make road trains.
Off-road trucks
Highway-legal trucks are sometimes outfitted with off-road features such as a front driving axle and special tires for applications such as logging and construction. Trucks that never use public roads, such as the biggest ever truck, the Liebherr T 282B off-road mining truck, are not constrained by weight limits.
Anatomy of a Truck
Almost all trucks share a common contruction: they are made of a chassis, a cab, axles, suspension and wheels, an engine and a drivetrain.
Chassis
A truck chassis consists of two parallel U-shaped beams held together by crossmembers. It is usually made of steel, but can be made (whole or in part) of aluminium for a lighter weight. The chassis is the main structure of the truck, and the other parts attach to it.
Cab
The cab is an enclosed space where the driver is seated. A sleeper is a compartment attached to the cab where the driver can rest while not driving. They can range from a simple 2 to 4 foot (0.6 m) bunk to a 12 foot (3.0 m) apartment-on-wheels. Modern cabs feature air conditioning, a good sound system, and ergonomic seats (often air suspended). There are a few possible cab configurations:
- Cab over engine or flat nose:
Where the driver is seated on top of the front axle and the engine. This design is almost umbiquitous 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 conventional cabs are the most common in North America.
- Conventional cab:
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—6-8 foot (1.73 m) or more—hood. With their very square shapes, these trucks offer a lot of wind resistance and can consume more fuel. They also offer poorer visibility than their aerodynamic or COE counterparts. By constrast, Aerodynamic cabs are very streamlined, with a sloped hood and other features to lower drag.
Engine
Trucks can use all sorts of engines. Small trucks such as SUVs or pickups, and even light medium-duty trucks in North America will use gasoline engines. Most heavier trucks use four stroke turbo intercooler diesel engines, although there are alternatives. Huge off-highway trucks use locomotive-type engines such as a V12 Detroit Diesel two stroke engine.
In the United States, on-highway trucks almost always use an engine built by a third party, such as Caterpillar Inc. or Cummins. The only exceptions to this are Volvo trucks and Mack trucks, which are available with Volvo and Mack diesel engines, respectively, and Freightliner, which is built by Daimler/Chrysler and is available with Mercedes-Benz diesel engines made by the parent company.
Drivetrain
Small trucks use the same type of transmissions as cars. Bigger trucks often use manual transmissions, which must be built stronger to withstand the torque their engines make. Common North American setups include 10, 13 and 18 speeds. Automatic transmissions for heavy trucks are becoming more and more common, due to advances both in transmission and engine power.
A vehicle body contains many openings apart from the vehicle doors. They include engine compartment hoods, hatch and tailgate openings, fuel doors, and battery access covers.
All of these openings have to be secured and may require a remote switch or lever to be activated. In some cases the activation is by cable, others may use electric or vacuum solenoids.
Some rear hatch openings have a hinged window incorporated, so the owner can have easy access without opening the entire door.
Engine compartment hoods may use single or double acting hinges. Their release may be located inside the passenger compartment, under the dash, in the glove compartment or on a doorjamb.
Some manufacturers are no longer fitting an engine compartment release to their vehicles. The hood can only be released by the manufacturers scan tool or by a service key fitted into a secluded opening on the vehicle body (usually behind a manufacturers badge). Before opening the engine hood on these vehicles, check the owner's manual, or the manufacturers manual, as unauthorized access may void any vehicle warranty.
