I suggest that you review Prof. Kamm's aerodynamic theories. I think that you will find that the traditional pickup truck CAN benefit from MY simple modification which smooths the airflow over the rear of the vehicle, taking full advantage of his theory. You know, the "large bubble of air" that exists in the rear of the vehicle that "aerodynamicists" claim to use as a design feature exists because of the 10 sq. ft of additional frontal area
created by having a tailgate in place. My boxes eliminate the "bubble" and drag and provide substantial gains in fuel economy. By the way, wind tunnel tests are generally conducted to determine improvements or enhancements.
Vehicles are NEVER designed with aerodynamics solely in mind. Aerodynamics is secondary to ergonomics, crash and powertrain package. There is a lot of room for improvements on ALL trucks.
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