Does driving in 4x4 actually use more gas than when not?

Question

Went skiing yesterday. Before leaving Lake Louise to drive back to Calgary I practically had to excavate my old 91 Ford Exploder from all the snow! Threw it into 4x4, and just left it in 4x4 for the whole drive. On the way I was eyeing the gas needle and wondering if it actually was going down faster than when I drive in 2x4. Not sure. I just remember that I heard some clown somewhere say something about you'll use the same amount of fuel because the transfer case is always moving, even when not engaged in 4x4. Seems fishy to me since if the transfer case indeed is already moving, but you the engage 4x4, then there's more of a LOAD, which mean more RESISTANCE, so more force needed to move the vehicle, so more fuel expended. Actually, wait...doesn't the transfer case just divide the power between front and back? I donno, I'm all messed up, what's the scoop people? Don't just say yes or no...explain it if you can)

Yeah...I'm pretty sure my pig drank more than usual...and yeah I know about only driving it in 4x4 on rough surfaces. 2 days ago, the Transcanada back to Calgary was like driving to see Santa at the north pole....during 10 back to back bizzards...inside Jupiter's anticyclonic storm.

Answer 1

When you're comparing otherwise-identical vehicles, and they're operated exactly the same, under exactly the same conditions, yes.

Ultimately, the extra fuel burn arises from drivetrain friction -- not just the mechanical friction of the drivetrain components (depending on your system, many or few of which may be disengaged from the engine when operating in 2WD) -- but also from the competition between the front and rear axles.

Slight variations in the loaded radius of your tires will occur during normal operation of your vehicle; in 2WD, these are normally magnified when turning in one direction with respect to the other, but nevertheless present when driving along a straight path -- so the differential is working (slightly) even when you're going straight.

When you shift into 4WD, the front and rear axles are mechanically linked through the drivetrain, and the vehicle tends either to attempt to pull itself apart or to squash itself together along its longitudinal axis -- and in curves, might even behave differently in this regard from side-to-side.

Ordinarily, these imbalanced forces are relatively small, but they nevertheless have a comparatively great influence on fuel economy.

Answer 2

On my truck it makes a fair difference but my truck has locking hubs so I can disengage it right at the wheels,then it is free rolling more like a two wheel drive. I'm not sure about an explorer if the tranfercase is allways turning with the axles...so now I'm curious, did you burn more fuel or not?
It's generally not a good idea to drive in four wheel drive unless the roads are actually slippery enought to absorb the load between the front and rear axles.
I figured the roads were bad in cowtown, I'm in Reddeer.

Answer 3

I drive Chevy Blazers as work trucks, have had 8 of them so far. I always figured 4x4 used more gas so I used it here and there.

I drive to another town often that is 100 miles away, driven it since I was a kid. I know exactly how much gas it takes in the Blazer to go that distance normally. Once I left it in 4x4 the entire trip without realizing it....it drank almost twice as much gas for the trip.

you tell me. now each 4x4 might be different depending on how its set up....and the same with all wheel drive. as subarus are AWD yet they don't suck gas like a semi.

Answer 4

In a nutshell: Yes!

Air Conditioning, increased altenator usage, and using 4 wheel drive all place a greater load on the engine.

Every extra gallon of fuel burnt puts 20 pounds more of CO2 in the atmosphere...

Did this help any?

Answer 5

Yes, driving in 4 will use more gas than driving in 2.
In 2, the front differential is freewheeling. In 4, it is engaged and that will create a load because the pinion/drive gear is not frictionless.

Answer 6

YES, but not like in ye olde day when 60, 70 , 80's when they had these huge crazy transfer cases. like my 80 full body jeep wagoneer now that sucks gas and you watch the needle move.. Today the extra fuel milage is very un-noticeable and its not a big deal like it used to be..

Answer 7

Of course it does there is more resistance on the road, so you need more power. therefore more fuel

Answer 8

of coars