Truck Towing Capacity: Are Two Trailers Allowed at Once?

Truck towing capacity is a crucial aspect of logistics and transportation, particularly when it comes to haulage and long-distance driving. Unlike what many might think, there are instances where multiple trailers can be attached to a single truck, a practice that is not only legal but also common in certain regions. This article delves into the legality, practice, and necessity of towing two trailers simultaneously, showcasing examples from various regions around the world.

Custom Horse Trailer Towing by Truck Drivers

The practice of towing multiple trailers is not limited to large-scale commercial operations. My son, a professional truck driver, pulled custom horse trailers for five years. With the proper permit, he managed to tow up to three trailers at the same time. He often embarked from Gary, Indiana, and delivered to New Mexico and Arizona, demonstrating the feasibility of towing multiple trailers under the right conditions.

Australian Road Trains: A Unique Practice

A notable example of towing multiple trailers is in Australia, where the concept of Australian Road Trains has become a prominent feature of transport logistics. Australian Road Trains are specialized vehicles that consist of a single tractor unit pulling up to four trailers. These trains can stretch up to 100 meters, significantly increasing the hauling capacity of a single vehicle. They are often seen in regional areas, tasked with delivering fuel, moving cattle, or transporting general freight.

The term road train in Australia is used quite frequently, and the practice is so common that one must give these enormous vehicles plenty of room when on the road. The unique design and size of these vehicles make them a common sight in the countryside, underscoring the importance of understanding local regulations and safe practices when encountering them.

Truck Towing in the United States and Beyond

In the United States, Canada, and Australia, there are various types of road trains, collectively known as 'doubles' and 'triples.' In the U.S and Canada, these formations are referred to as 'doubles,' 'triples,' or even derogatorily as 'wiggle wagons' due to their vulnerability to high winds. In Australia, the term 'road train' is universally used. Moreover, different types of doubles are employed for various purposes:

Traditional Doubles feature a 28.5-foot long trailer with a flat load floor. Federal Express Pups are like traditional doubles but with a "package belly" and a roller bed to fit additional packages, an arrangement exclusive to FedEx Ground. Extra Long Doubles (Texas Doubles) are a specialized version measuring 33 feet per trailer and only permitted in the state of Texas, primarily for FedEx and some food service distributors. Rocky Mountain Doubles involve a 53-foot conventional trailer and a shorter companion trailer, commonly seen in Western U.S. states and parts of Canada. Triples utilize a set of traditional doubles or Federal Express Pups with a third trailer attached for extra capacity. B Doubles are predominantly utilized in Canada. Turnpike Doubles comprise 53′ or 40′ trailers coupled together for exceptionally long hauls, found only on a few toll roads in the U.S. Road Trains in the Australian Outback refer to any configuration of 2 or more trailers.

These formations are designed for specific purposes and regions, each with unique features and regulations. The dolly connecting trailers, for example, can weigh as much as a mid-sized or full-sized sedan. It’s important to understand that moving this dolly on flat ground is relatively straightforward but can be challenging on an incline. Special care and training are essential for safe operation.

UK Regulations on Truck Towing

Near the United Kingdom, the rules governing the towing of two trailers are slightly different. Any vehicle is legally allowed to tow two trailers, though there is a speed restriction of 20 miles per hour, which can make it economically unfeasible for long haul operations. However, there is a potential shift on the horizon as Welsh truck drivers may start adopting this practice, potentially impacting the haulage industry in the region.

Conclusion

The practice of towing multiple trailers is a sophisticated and effective solution to maximizing cargo capacity, particularly in regions with extensive distances and specialized transportation requirements. Understanding the regulations and realities of towing multiple trailers is vital for truck drivers and logistics companies alike. Whether you're in the U.K., the U.S., Canada, or Australia, the key is to remain informed and prepared to navigate the unique challenges and opportunities presented by these unique vehicles.

Additional Resources

For more detailed information on truck towing regulations and practices, consider checking the following sources:
- Transport UK
- FedEx Road Trains
- Australian Road Safety Bureau