Gas Miliage Drop Roof Rack

Some drivers may see their gas mileage drop by as much as 20 percent depending on vehicle type and type of roof rack.

Gas miliage drop roof rack.

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. Their study was published recently in the journal energy policy in a paper titled fuel consumption impacts of auto roof racks. 6 0 l 100 km approx. 5 6 l 100 km approx.

Roof rails will not effect mpg cross bars may to some degree and mostly is not only while traveling at a freeway speeds. Drag coefficient increases by speed squared. Of course no one in their right mind would drive around with an oversized pool float fastened to the roof of their car while it s. 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.

If most of your driving is freeway and you re worried about 2mpg then take the cross bars off when not in use. 42 mpg roof rack with thule dynamic 800 aerodynamic cargo box. I ve put cross bars on two different odys with no measurable effect on mpg. It caused a whopping 34 percent drop in fuel economy or 10 mpg.

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. Your fuel cost is ten cents mile or 1 500 year. 39 mpg thus the cargo box on the roof increased fuel consumption by about 5 compared to the baseline. So it varies depending on the vehicle on the rack and on the driving highway or city but it s at least five percent and probably a lot more.

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. Mileage went from 41 mpg at 65 mph to 40 mpg. 5 9 l 100 km approx. The empty roof rack had a nearly 2 percent impact on fuel economy which translates to a little more than three quarters of a gallon of gas.

Generally adding a loaded roof rack to your car will lower your gas mileage by at least 10 percent.