At Great Dane, we’re always looking for ways to help you operate more efficiently, and that includes how trailers interact with the air. You may not be able to see it, but we all feel its effects. On the road, good aerodynamics translates into real-world savings and performance gains.
We spoke with Barry Personett, our Vice President of Product & Sales Engineering, as well as Chris Lee, our Vice President of Engineering, to get a closer look at how aerodynamics are shaping trailer design and what fleet owners need to know to get the most out of every mile.
Why Aerodynamics Matter
Whether you’re working in long-haul trucking or regional delivery, the role of aerodynamics is simple: reduce drag and improve fuel efficiency. But what about the effect it can have on your bottom line? It’s more than you might think.
“Aerodynamic devices are added to our trailers to reduce drag and improve fuel efficiency,” Personett explained. “Devices are required to prove their ability to reduce fuel consumption through CARB and the EPA.”
He’s referring to verified programs like the EPA’s SmartWay initiative, which tracks the performance of various aerodynamic technologies. You can read more about that here, but the bottom line is clear: the right equipment can lead to meaningful fuel savings, especially on long-haul routes where higher speeds enhance the impact of aerodynamics.
Which Trailers Benefit Most?
In most cases, it doesn’t matter whether your trailer is hauling food, paper products, or cleaning supplies—if you’re running dry vans or reefers across an interstate at more than 55 mph, aerodynamic devices can make a big impact. On the other hand, there is one type of trailer that typically doesn’t use these kinds of components.
“Flatbed trailers rarely include aero devices,” Personett said. Flatbeds — despite generally not having much surface area on their own — often haul irregularly shaped equipment, which collides with the air and creates additional drag.
“But for standard vans and reefers, it’s common to see side skirts and rear fairings added to improve airflow,” he added.
That’s because box-shaped trailers present a consistent profile where drag reduction can be optimized. Box-shaped trailers have long, uninterrupted sides. Removing unnecessary gaps can make it easier for air to flow over, along, and under these trailers, increasing efficiency.
Whether you’re pulling a Champion dry van or an Everest reefer, integrating the right aerodynamic features can pay off in both fuel efficiency and environmental impact.
What Devices Make the Difference?
When it comes to practical aerodynamic upgrades, there are two workhorses that stand out: side skirts and rear fairings.
“The side skirt is one of the most popular devices used today,” Lee said. “Depending on the configuration and application, the side skirts available in the market can provide 3-9% fuel savings.”
“Skirts smooth the airflow under the trailer and around the running gear components,” Personett added. “Rear fairings help break up the vacuum effect at the blunt rear end of the trailer.”
Both work in tandem to reduce resistance from airflow, helping your trailer move with less effort. Even small improvements in drag can translate to big fuel savings across hundreds of miles.
Modifying the roofline or tapering the rear of the trailer could, in theory, also help reduce drag — but as Personett noted, those changes often aren’t practical.
“Tapering the rear would make a difference,” he said, “but it would affect the openings, and that is not typically acceptable to trucking operations.”
Balancing Benefits with Practicality
While the fuel savings are attractive, it’s important to think through how aerodynamic add-ons might affect your operation in other ways. Weight and maintenance are two key factors to consider.
“Fleet owners need to consider the added weight of the device or devices,” Personett explained, “and the maintenance they might require over time.”
In many cases, those considerations are more than worth the trade-off, but it’s important to spec your trailer with the full picture in mind. We work directly with our customers to make sure every feature, including aerodynamics, matches the way your fleet operates.
Looking Ahead
As the industry moves toward more sustainable and efficient operations, we expect to see growing interest in aerodynamic innovations — especially in combination with electric and hybrid drivetrains. Active aero systems and new lightweight materials are already being explored, and we’re staying ahead of those trends to make sure our trailers continue to support the needs of modern fleets.
If you have questions about optimizing your trailer specs for fuel efficiency or want to understand what aero packages might make sense for your operation, we’re always here to help. Because at the end of the day, every little bit of air you don’t have to fight helps keep your fleet moving forward.
Contact us today to learn more about improving your fuel efficiency.
