Heavy duty service trucks come in a wide variety of configurations and sizes to serve a wide variety of needs. Service trucks can be generalized for all purpose contractors and construction or they can be very specialized to meet highly specific uses such as firefighters and rescue workers.
Heavy duty service trucks are generally built for work. They come standard with heavy duty suspension and special accessories to carry the tools of the trade from ladders to booms and buckets. Service trucks are usually custom made, frequently starting with a standard heavy duty truck or van and then customizing the bed to meet the needs of the end user.
The major US manufacturers of heavy duty truck that are customized into service trucks are the GMC heavy duty trucks from General Motors and F-450 Super Duty trucks from Ford.