How Trucks Work

It would be impossible to provide great detail in this page, however, this page will provide an overview.

The main structure of a truck is the chasis. this is a simple steel structure consisting mainly of two parallel beams running front to back and upon which the truck is built. On the outside, the cab is the most noticeable, since the engine etc. is located under it. The cab is basically an enclosed space where the driver has various controls ergonomically located around the driving position. the cab also has storage and comfort measures such as heating and in some modern cabs, air conditioning. In a sleeper cab, the bunk(s) are also within the cab.

The engine is the heart of the truck and is where the power to move the truck is generated. This power is transmitted to the tyres through a clutch, gearbox and differential. The range of gearing allows the engine to pull heavy weight from a stand still to moving, and as the gears are changed, turn the wheels faster. The engine is fueled by diesel and air. This mixture is compressed in the cylinders until it explodes, creating the energy.

Once the power is transmitted to the wheels, the truck will move forward. To allow the truck to turn more easily, power steering using hydraulics power assistance helps the driver and the differentials allowing each side of the rear axles to turn independently helps the tractor to corner with less resistance.

Braking on a modern truck will be via drum or disc brakes. unlike on a car, the brakes are applied using air. Another difference is that with no air, the brakes are applied, as air is built up, the brakes are released. Modern trucks have electronically controlled braking to aid safety. these systems sense pressures and adjust the braking accordingly. To save wear and tear of tyres and brakes, many heavy trucks have engine brakes which use compression to retard the engine.

The above outline obviously simplifies what are quite complex machines. On board computers are now common and telematics systems are being fitted as standard. There are many vacancies for HGV Mechanics and the working environments for these advanced technology machines are far different from the grubby garages of the past.