Roof Box Fuel Efficiency

5 6 l 100 km 42 mpg roof rack with thule dynamic 800 aerodynamic cargo box.

Roof box fuel efficiency. As the british magazine what car. 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. Their study was published recently in the. Do ski racks and roof boxes hurt fuel efficiency.

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. 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. 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. 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.

Yes more than you think. The roof rack mpg experiment he compared the gas mileage of his car at 54 7 mph 88 kph with 1 no roof racks 2 an empty roof rack and 3 a mountain bike on the roof rack.