There are two main types of modern log trucks - those that are used on rough ground and the paths in the forest where they are cut, and those used for transport on regular highways and roads. [5] The suspension and tires of an offroad truck are particularly important, as the roads in the forest are hilly and often temporary. Robust, low pressure and high pressure tires are used. Up to nine axles can be used to provide low ground pressure and good traction. [6]
Timber is often grown in a hilly country unsuitable for farming, and so the ability of a logging truck to climb the slope is essential. Steepness depends on the quality of the surface - mud and snow are more difficult to climb than gravel and soil. For a manageable slope, the speed will depend on the power of the truck. [7] Legal weight limits will vary by jurisdiction, but range from 80,000 to 88,000 pounds (36,300 to 39,900 kg) - about 40 short tons (35.7 long tons; 36.3 t), for example, in the southern states of the USA. . [8]
One or more cranes or winches can be attached to the truck to load logs. The logs are usually emptied by allowing them to roll sideways.
