The Americans for Modern Transportation coalition released a new study finding that twin 33-foot trailers would boost safety and efficiency with widespread adoption.

The study, entitled Twin 33 Foot Truck Trailers: Making U.S. Freight Transport Safer and More Efficient, was conducted by Ronald Knipling, a 35-year traffic safety researcher. In it, Knipling found that twin 33s improved safety primarily through road stability and cutting down on the number of trucks on the road.

Because trailers often fill up before hitting the 80,000-pound limit, according to the study, by switching from twin 28-foot trailers to twin 33s, cargo volume could increase by 18.6% while still not needing to increase the maximum weight limit. This means that using twin 33s would require 15.7% fewer trucks and trailers to carry the same amount of cargo.

“Allowing widespread use of Twin 33 trailers is common sense policy. Not only are they more stable at highway speeds, the efficiency gains mean we have fewer trucks on the road,” said Knipling. 

“Fewer trucks means fewer accidents, less wear and tear on our roads, and more focused enforcement by weigh stations for all types of trucks. It’s a win-win for drivers, consumers, businesses, and the economy.”

The study found that through a widespread adoption of Twin 33s, truck miles driven could have by reduced by as much as 3.1 billion miles and reduced the number of truck-involved accidents by 4,500 annually.

Fewer trucks on the road would also reduce fuel use, saving 255.2 million gallons of fuel and reducing carbon emissions by nearly 3 million tons. The effect of this reduction would be similar to taking 551,000 cars off of the road, according to the study.

Another positive change by switching to twin 33s was reduced congestion, again from needing fewer trucks on the road to move freight. The study estimated that Twin 33s could have decreased travel delay time by 53.2 million hours over the course of a year. Ultimately, all of the positives resulting from twin 33s could have saved around 2.6 billion in transportation costs.

The study also highlights other innovations in trucking safety and efficiency such as adaptive cruise control, electronic stability monitoring, video mirrors, collision warning systems and onboard safety monitoring.

“While the trucking industry continues to innovate, it’s been more than 25 years since we upgraded our transportation policies,” said Melissa Manson, AMT spokesperson. “Business and consumer trends demand a modern transportation system.”