I've been looking on the gov's fuel economy website at the ford rangers and found there's a 3mpg difference for highway between a 4x4 and 2wd. I understand that there's a weight difference in the 4x4 for the transfer case and other 4wd parts but is that where the loss of fuel economy comes from? Sorry if this delves into an old thread that I haven't seen but I'm a new guy around here.

Thanks!

 

Most likely added frictional losses due to the transfer case, front axle, and possibly tire size? Maybe some little bit of aerodynamics come into factor, if the 4x4 sits a bit higher?

Jimmie

 

I'm sure it's a combination of a few different things, but mostly has to do with the live axles they have.

 

Even 4WD with unlocking hubs get less mileage than 2WD. I was told by a Ford engineer that the front live axle only costs about 0.3 mpg.

I think the extra weight of the front drivetrain is the biggest factor in loss of mpg in 4WD vehicles. Of course, larger tires and the higher ride height are contributing factors.