Roof Box Fuel Efficiency

Adding a roof box means your car has to carve a bigger hole in the air which requires burning more fuel so your mpg will suffer.

Roof box fuel efficiency.

Do ski racks and roof boxes hurt fuel efficiency. As the british magazine what car. He found that compared to the baseline of no roof rack the empty rack reduced his mpg by 12 7 and the roof rack with a bicycle reduced it by a whooping 27 3. They found that in 2015 roof racks nationwide were responsible for 0 8 percent of light duty vehicle fuel consumption or 100 million gallons of gasoline.

It s impossible to give an exact figure because it depends on so many factors but britain s biggest roof box manufacturer thule states that your mpg is unlikely to decrease by more than 5. 5 9 l 100 km 40 mpg roof mounted thule xtender 739 ski carrier with skis. Their study was published recently in the. Recently found adding properly fitted roof boxes and a modest amount of cargo to a couple of compact family models decreased their effective gas mileage by up to.

6 0 l 100 km 39 mpg thus the cargo box on the roof increased fuel consumption by about 5 compared to the baseline. Adding any rooftop carrier cargo box or ski rack to your car significantly cuts your highway mileage all the time it.