There are two main types of modern logging trucks – those used on rough ground and forest trails where they are cut, and those used for transport on regular highways and roads.
The suspension and tires of an offroad truck are especially important, as roads in the forest are bumpy and often temporary. Robust low-pressure and high-pressure tires are used. Up to nine axles can be used to provide low speed ground pressure and good traction.
Timber is often grown in hilly country unsuitable for farming and so the gradient of a logging truck is important. The steepness depends on the quality of the surface - mud and snow are more difficult to climb than gravel and soil. For a manageable gradient, the speed will depend on the power of the truck.
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) in the southern US states, for example.
One or more cranes or winches on the truck to load the logs. Logs are usually unloaded by allowing them to roll sideways.
