FlowBelow AeroFender Delivers 1.44% MPG Boost
FlowBelow said that independent testing by Mesilla Valley Transportation Solutions confirmed that its new AeroFender aerodynamic device saved 1.49 gallons of fuel for every 1,000 miles driven.

The McLane Company has been testing the AeroFender since 2021 and has accumulated millions of real-world miles using the device.
Photo: FlowBelow
FlowBelow Aero, a developer of tractor and trailer aerodynamic technologies, has introduced its AeroFender. The device is the newest product in FlowBelow’s aerodynamic equipment lineup.
In a press release, FlowBelow said the AeroFender has been tested and is now widely available at OEM mod centers for installation on new trucks. It can also be ordered directly from FlowBelow or thru the OEM dealer network for retrofit applications.
Controlled Track Testing
According to FlowBelow, the AeroFender reduces drag on day- and sleeper-cabs. It is also an important tool fleets can use to improve fuel economy and to reduce CO2 emissions.
The low-profile device provides the same safety and operational benefits as a traditional quarter fender. But, the company said, it also improves fuel efficiency by re-directing the airflow ahead of and around a power unit’s leading drive axle.
FlowBelow reports that at a controlled track test completed in November 2023 by Mesilla Valley Transportation Solutions, the device was proven to save 1.49 gallons of fuel for every 1,000 miles driven. This resulted in a 1.44 percent improvement in fuel economy overall.
FlowBelow said fleets can expect a truck with an AeroFender installed and traveling 125,000 miles per year to save an estimated 187 gallons of fuel and approximately 4,207.5 pounds of CO2.
At 22.5 pounds of CO2 per gallon of diesel fuel, a fleet of 1,000 could reduce its CO2 emissions by as much as 4,207,500 pounds, or 2,103.75 tons, according to the company.
In addition to the associated fuel savings and environmental upsides, FlowBelow calculates that the ROI on its AeroFender will come in at under one year from the date of its installation.
Millions of Real-World Miles
McLane Company has been a user of FlowBelow’s Tractor AeroKit and trailer wheel covers for some time. In 2021 the fleet was an early adopter of the AeroFender in advance of its release to the industry at large.
“After extensive durability testing and ROI cost analysis, we began putting FlowBelow AeroFenders on our fleets in 2021,” said Daniel James, director of transport and tech at McLane. “The technology has proven itself over many years and millions of miles. We continue to spec it on all new vehicles to help us save fuel and reduce the environmental impact of our fleet.”

The AeroFender from FlowBelow improves fuel efficiency by re-directing the airflow ahead of and around a power unit’s leading drive axle.
Photo: FlowBelow
McLane proved to be an ideal test case for the AeroFender, FlowBelow said. The exposure to a wide variety of drivers, environmental factors and driving conditions provided valuable insights and solidified FlowBelow’s confidence that the AeroFender would be very attractive to fleets.
“We have over 1,200 units in the field, and we’re excited to begin offering it to a broader spectrum of fleet customers,” said Josh Butler, FlowBelow president and CTO. “We believe it will offer great appeal to LTL and day cab fleets, which is a sector of the market that has not traditionally been as likely to utilize our flagship Tractor AeroKit. The AeroFender is extremely durable, easy to install, and a smart upgrade to a component that these fleets are already buying.”
As a final step, FlowBelow decided to conduct independent testing that would add an objective point of view and statistical analysis to the equation. It chose Mesilla Valley Transportation Solutions, a provider of breakthrough fuel economy testing and design and development services for the trucking industry, to put the AeroFender through its paces.
“FlowBelow’s mission is to help save fleets 500 million gallons of fuel by 2030. Introducing the AeroFender makes that goal more attainable,” said Ted Simmonds, CEO of FlowBelow. “New product innovation is what drives us. We focus our efforts on developing products that not only help fleets save fuel, but also help them advance their sustainability objectives.”
The AeroFender is available for purchase thru OEM mod centers for installation on new trucks, or directly from FlowBelow or thru the OEM dealer network for retrofit applications.
The compete MVT Solutions test report can be found here.
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