How Much Do Roof Racks Affect Gas Mileage

Mileage went from 41 mpg at 65 mph to 40 mpg.

How much do roof racks affect gas mileage. Their study was published recently in the journal energy policy in a paper titled fuel consumption impacts of auto roof racks. The control test the tourx without roof rails. If most of your driving is freeway and you re worried about 2mpg then take the cross bars off when not in use. 5 6 l 100 km approx.

5 9 l 100 km approx. Off the showroom floor the regal tourx gets 21 miles per gallon in the city and 29 mpg highway for a combined fuel economy of 24 mpg. Your fuel cost is ten cents mile or 1 500 year. 6 0 l 100 km approx.

Generally adding a loaded roof rack to your car will lower your gas mileage by at least 10 percent. Some drivers may see their gas mileage drop by as much as 20 percent depending on vehicle type and type of roof rack. 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. So if your car usually gets 30 mpg on the highway and you add a full roof rack your highway gas mileage will drop to 24 27 mpg.

42 mpg roof rack with thule dynamic 800 aerodynamic cargo box. 40 mpg roof mounted thule xtender 739 ski carrier with skis. And since air resistance increases exponentially with speed the difference would have been even bigger at 70 mph many people drive at that speed. Drag coefficient increases by speed squared.

39 mpg thus the cargo box on the roof increased fuel consumption by about 5 compared to the baseline. Their study was published recently in the. I ve put cross bars on two different odys with no measurable effect on mpg. This editor many years ago in a move across the country to oregon from michigan found that the highway mileage of a four cylinder accord dropped from more than 40 mpg down to 32 mpg with a.

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. Roof rails will not effect mpg cross bars may to some degree and mostly is not only while traveling at a freeway speeds. Some roof racks have cross members that can be unscrewed and stowed inside.