As a noun, the term means the lower part of the truck where the logs rest while being hauled. The crossbeam has two upright stakes which keep the logs contained.

As a verb, the term means to carry the empty trailer on the tractor unit for a return to the woods. hauling a trailer back to the woods unbunked is considered unsafe as it bounces and jumps about. The only log hauling truck not carried back bunked is a hayrack.

In this configuration, the logging truck makes a very compact vehicle and with the horsepower to weight ratio available to it, and the friction from 10 tires onthe road, there are few passenger cars which can stay in front of an empty logging truck on a curvy, mountain road. Just best to pull over and get out of the way!