How much does putting a camper shell on a pickup truck impact gas mileage?
It would depend on the construction and type of camper shell. A shell that conforms to the height and width of the cab (which is commonly referred to as a truck cap) will not really affect it much, however if you are talking about a camper shell that is taller than the truck cab or an actual slide in camper for your pickup you will see a noticeable difference in milage from the wind resistance.
