A class A truck is commonly a very large type of truck such as a semi-tractor or a large cement mixer, dump truck or mobile crane. The driver of a class A truck must possess a special driver's license demonstrating that the driver has had sufficient training in the operation and general safety of the vehicle. Typically equipped with air brakes and large diesel engines, the class A truck can have transmissions with more than 20 forward gears and three or more reverse gears all designed to allow the large truck to use its power to the fullest and most efficient manner when dealing with heavy loads.
Unlike a common driver's license, the operator of a class A truck is tested on the operation and serviceability of the air brake system, fuel system as well as the application of tire chains in some areas. This commercial driver's license, or CDL, as it is more commonly called, is awarded to the driver of a class A truck only after he or she attends and successfully graduates from a truck driving program. This program teaches prospective truck drivers not only how to drive and back up a class A truck, but it also explains the purpose and method of filling out driver's logs and weight distribution when loading the trailer.
There are many types of class A truck other than the common semi-trucks that are seen traveling the highways of the world. Many of the larger cement and gravel hauling trucks are class A type trucks requiring the driver to possess a CDL. Some of the largest fire engines are also class A-rated and require that the fireman that drives the truck be specially trained as well. Commonly, the air brake system is the defining system that separates a class A from a class B truck in most areas.
Many of the long-haul semi-trucks are like rolling motel rooms complete with beds, television and even microwave ovens. These class A truck units are often on the road for weeks at a time and require all of the special options to enable the driver to rest, eat and relax while taking a break from driving. Many of the drivers of these long-haul trucks work in teams with one driver driving while the other is sleeping or resting. This allows the class A truck to remain in motion and work virtually nonstop, thus letting the owner of the truck make the maximum amount of money the truck can earn.