Affect of Roofbox on fuel consumption
#1
Super Member
Thread Starter
Affect of Roofbox on fuel consumption
We make the same trip every year from Canada to USA. Up until this year, we did it with roofrack and Thule box. Two in car, rear seats down and cargo of normal stuff - suitcases, golf clubs, etc.
In past years, mileage on trip down was about 31.5. Then once unloaded and perhaps using non-winter fuel, about 32mpg down here with 90% highway. This year without roofbox, mpg improved to 33.5 on way down and about 34.5 down here in SC. Nothing like some claim, but better that in past. Our mpg since last reset over a year ago, is 33.1. In summer in Canada we do a lot better. (36+mpg on highway)
In past years, mileage on trip down was about 31.5. Then once unloaded and perhaps using non-winter fuel, about 32mpg down here with 90% highway. This year without roofbox, mpg improved to 33.5 on way down and about 34.5 down here in SC. Nothing like some claim, but better that in past. Our mpg since last reset over a year ago, is 33.1. In summer in Canada we do a lot better. (36+mpg on highway)
#3
Super Member
Thread Starter
#4
Super Member
Haven't put anything on top on mine but I skied a lot driving a domestic SUV throughout the West. Some trips with ski racks on top and others without. I attributed a difference of 3mpg to anything on top, even the empty racks. Didn't take long to pack with skis inside. Depending on traffic I've gotten right a 40mpg on my GLK. Shorter trips with traffic or hills and curves I've gotten as low as 32mpg.