[D K]

Does 4wd affect fuel mileage much?

 

[Boocoodinkydow]

There is a rated difference of 1 mpg. With so many variables I doubt even a side by side comparison would be conclusive. My educated guess, theoretically, the 4x4 would suffer slightly but not enough overlook the option if the need is there. I've had it on my last 2 trucks & have yet to use it on either but it's reassuring to have it.