One cap vendor posts this on their web site:
Quote:
|
Documented tests confirm that the aerodynamic enhancements gained over open-bed pickups reduce the vehicle’s coefficient of drag and boost gas mileage.
|
source:
Snugtop - Custom Fiberglass Manufacturing, Truck Cap & Tonneau Top Covers, Camper Shells Tops, Customized Truck Toppers, Pick Up Truck Canopy
... and of course provides no additional information about the tests. (Wonder if they're referring to the Pop Mech article....)