Does a camper shell affect gas mileage?

Yes, a camper shell can affect gas mileage. Adding a camper shell to a vehicle increases its weight and aerodynamic drag, both of which can result in a decrease in fuel efficiency. The exact impact on gas mileage will vary depending on the size and weight of the camper shell, the shape of the vehicle, and driving conditions. In general, the heavier the camper shell and the more aerodynamic drag it creates, the greater the decrease in fuel efficiency will be.

For example, a study by the United States Department of Energy found that adding a camper shell to a Ford F-150 pickup truck reduced its fuel efficiency by about 2 to 3 miles per gallon. The study also found that the impact of a camper shell on fuel efficiency was greater at higher speeds.

However, it's important to note that adding a camper shell can also have some benefits, such as providing additional cargo space and improving the vehicle's handling and stability. Additionally, if the camper shell is designed to be aerodynamic, it may have a minimal impact on gas mileage or even improve it in some cases.