FlowBelow Aero recently introduced a redesigned version of its Trailer AeroSlider, an update that saves 3.0 gallons of fuel for every 1,000 miles a trailer travels, according to the company.
The launch arrives in the most expensive stretch for diesel on record.
The AeroSlider targets the area around the trailer tandem, where exposed wheels, suspension and underbody components sit in the airflow. The system combines FlowBelow trailer wheel covers, flow-through mud flaps and rear fairings. Rather than shielding those components from the air, the fairings direct air leaving the tandem slightly outward and rearward, which FlowBelow said dilutes the trailer wake and reduces turbulence around the wheels and suspension. Because the hardware mounts to the sliding suspension and travels with it, the company said the savings continue when a fleet repositions the tandem for different loads and axle-weight requirements.
In June 2026, MVT Solutions ran fuel economy testing with 2019 International LT tractors pulling loaded 53-foot dry van trailers. The baseline configuration in that test already carried side skirts and trailer wheel covers. Adding the AeroSlider’s rear fairings and flow-through mud flaps to that baseline saved 1.77 gallons per 1,000 miles, according to the company. In separate testing, MVT Solutions measured 1.23 gallons per 1,000 miles from FlowBelow trailer wheel covers. FlowBelow adds the two results together to reach the 3.0-gallon total, so a fleet reaching that number is buying the full package rather than the fairings alone.
Josh Butler, FlowBelow president and chief technology officer, said the company designed the system to pay for itself in less than 18 months for a typical regional or long-haul fleet with diesel at $3.00 a gallon. At current fuel prices, Butler said, payback can fall below 12 months, even for fleets whose trailers travel as little as 30,000 miles a year. He pointed to trailer side skirts as the precedent, a product that reached wide adoption because the fuel savings justified what fleets paid for it, and said FlowBelow sees the AeroSlider as “the next practical step fleets can take to reduce trailer drag.”
