That absolute block of a Dodge semi truck in yesterday’s video reminded me how much aerodynamics had once been important in the trucking industry—beyond just the styling—and then was totally abandoned before being embraced so vitally in more recent decades. This 1935 Studebaker sleeper semi truck and trailer show that to good effect. That sloping trailer front contributed substantially to its aerodynamics, just like the big sloping fairings on modern semi tractors.
I’m referring to the Dodge LNT like this one, but that space-saving boxy style was almost universal at the time, given the very cheap diesel fuel, which commonly cost less than half of the price of gasoline.
One of the more interesting early approaches to improving aerodynamic efficiency after the energy crisis was the GMC Aero Astro, which had a fairing that could be raised or lowered according to the size trailer it was hauling. Apparently it did not catch on. But then the switch to conventional tractors was under way, and they utilized fairings a bit differently.
Apparently the Kenworth T680 is the most aerodynamic truck in current production, but I suspect the differences with its competition are minimal.
That will undoubtedly change when the Tesla Semi arrives. It is going into limited production later this year, as it will utilize the new larger format 4680 cells. Range was projected at either 300 or 500 miles, depending on battery pack size, but in November of 2020, Musk said it may be as much as 621 miles.