Gas Mileage 4x4 Vs. 2x4?

[MB4x4]

A friend of mine told me that a 4x4 truck's gas mileage is worse than the gas mileage of a 2x4 truck, even though if the 4x4 is shut off.

How big is the difference really (if there is one)?

[95Sierra2500]

Well, I dunno, I've never driven a 2x4 down the road. I've driven 4x2's though. A 2x4 is a board, a 4x2 is a vehicle.

 

As for the mileage difference, it depends on the setup. For example, there's about a 2-3 mpg difference between a GM 4x4 and a GM 4x2 truck that are otherwise identical. That's because when a GM truck disengages its 4-wheel drive, the front axles and much of the front drivetrain is still engaged and turning (extra rotational mass, kills mileage). Older GM's with the solid front axles, or most current Fords, are down to a 1mpg difference because all that rotational mass is disengaged so that only the front wheels turn. Now you're just carrying around extra dead weight, which doesn't affect mileage as much as rotational mass does.

 

Cliff notes: Your friend is right, though the amount varies based on the design.

[VMax2007]

Well, I dunno, I've never driven a 2x4 down the road. I've driven 4x2's though. A 2x4 is a board, a 4x2 is a vehicle.

 

Dammit Tim, ya beat me to it.

[Nick The Great]

Well, I dunno, I've never driven a 2x4 down the road. I've driven 4x2's though. A 2x4 is a board, a 4x2 is a vehicle.

 

Yeah, 4 of the 2 wheels spin. I have always wondered why it is 4x2 and not 2x4. Is it to avoid such confusion with the lumberyards?

 

[HawkeyeOC]

Well, I dunno, I've never driven a 2x4 down the road. I've driven 4x2's though. A 2x4 is a board, a 4x2 is a vehicle.

 

Yeah, 4 of the 2 wheels spin. I have always wondered why it is 4x2 and not 2x4. Is it to avoid such confusion with the lumberyards?

 

 

 

It can be both if you prefer. Just carry around some 2 x 4s in your 4 x 2 and you can have the best of both worlds

[redvett]

GMT800 & up have about a 1 mpg difference.

[Nick The Great]

Well, I dunno, I've never driven a 2x4 down the road. I've driven 4x2's though. A 2x4 is a board, a 4x2 is a vehicle.

 

Yeah, 4 of the 2 wheels spin. I have always wondered why it is 4x2 and not 2x4. Is it to avoid such confusion with the lumberyards?

 

 

 

It can be both if you prefer. Just carry around some 2 x 4s in your 4 x 2 and you can have the best of both worlds

 

 

That's why I got rid of my 99, it was 2 wheel drive.

 

This one is 4x4. Not a problem. Unless you're building a fence or something . . .

[davzog]

It used to be that a 4x4 used a lot more gas than a 4x2 (or 2x4 - couldn't resist)....2-5 mpg in some cases.

 

The factories have made great strides to get them closer together. When disengaged there is typically about 1 mpg difference....you still have to carry the weigt of the front differential whether or not it is engaged (but not married - ha - couldn't resist)

 

I bought a 4x2 because the weight difference lowered the towing capacity of my HD2500 though not by a whole lot...just that my wife carries a bunch of stuff.....

 

Short answer - 4x4 costs mpg....not much in today's technology.

[zxcv]

It used to be that a 4x4 used a lot more gas than a 4x2 (or 2x4 - couldn't resist)....2-5 mpg in some cases.

 

The factories have made great strides to get them closer together. When disengaged there is typically about 1 mpg difference....you still have to carry the weigt of the front differential whether or not it is engaged (but not married - ha - couldn't resist)

 

I bought a 4x2 because the weight difference lowered the towing capacity of my HD2500 though not by a whole lot...just that my wife carries a bunch of stuff.....

 

Short answer - 4x4 costs mpg....not much in today's technology.

 

 

 

I think it would have been easier if you just typed "2wd".

 

Anywho, in the winter here I would almost put money down that 2wd trucks get worse fuel mileage than 4x4's. MPG decreases a little bit when you are in the ditch with the tires spinning!

 

 

As for the gas mileage of 2x4's, I would have to give an educated guess 8.938 units.

[music]

I went from a '99 4x2 to a '08 4x4, both with a 5.3L. The '99 had a 3.42 rear, the '08 has a 3.73 and AFM. At most, I've seen ~1 mpg difference around town, and no difference on the highway. That's just how it worked out for me, for what it's worth.

[PasoRoblesJimmy]

In bad weather give me a 4x4!!!! The last 4x2 I owned got stuck in the snow in the middle of nowhere and required towing by a 4x4 2-times in the same day. I sold that 4x2 as soon as I could find and buy a 4x4 to replace it. You are lugging about 500 more pounds of weight in a 4x4 than in a 4x2. Who really cares about a small penalty in gas mileage? Four wheel drive beats the daylights out of being stuck out in the middle of nowhere and freezing your tush off while waiting around for a 4x4 to come and rescue you.

[04Sierra_Z71]

as stated before a 4wd typically weighs more and more drivetrain loss than a 2wd. On a 4wd you have the transfer case that is bolted just behind the transmission so power goes through the transmission and into the transfer case then goes out the front and out the rear, now the transfer case is what engages the 2wd-4wd modes so inside it spins all the time, now in theory in 2wd mode only the shaft going out the rear should spin but thats not always true, on gm's there are no lockout hubs on the front wheels so when the front tires turn they turn the front diff. which then rotates the front driveshaft and then into the transfer case, so naturally a 4wd has a lot more drivetrain loss vs a 2wd which they are simple as can be the power goes straight through the transmission then the driveshaft and rear end so very little is actually lost, also you have to factor in the tire size as well and usually 4wd's will have bigger size tires and typically an all terrain style tread whereas a 2wd will normally just have straight tread for the road. Typically you'll loose 2-3mpg and in some cases as much as 5mpg difference between the two.

[2018GMC]

as stated before a 4wd typically weighs more and more drivetrain loss than a 2wd. On a 4wd you have the transfer case that is bolted just behind the transmission so power goes through the transmission and into the transfer case then goes out the front and out the rear, now the transfer case is what engages the 2wd-4wd modes so inside it spins all the time, now in theory in 2wd mode only the shaft going out the rear should spin but thats not always true, on gm's there are no lockout hubs on the front wheels so when the front tires turn they turn the front diff. which then rotates the front driveshaft and then into the transfer case, so naturally a 4wd has a lot more drivetrain loss vs a 2wd which they are simple as can be the power goes straight through the transmission then the driveshaft and rear end so very little is actually lost, also you have to factor in the tire size as well and usually 4wd's will have bigger size tires and typically an all terrain style tread whereas a 2wd will normally just have straight tread for the road. Typically you'll loose 2-3mpg and in some cases as much as 5mpg difference between the two.

 

Automatic Locking/Unlocking Hubs

 

This just lets the front tires turn like a 2wd.

 

Hands down I will always buy a 4wd - Even if I only use it once a year!

 

Resale values of 2wd trucks suck, its always harder to sell a 2wd than a 4wd. Unless you live in a climate where it never snows.

 

Getting stuck in a parking lot space because you are on a patch of ice is just embarrassing!

[JoshRDavis.84]

I've used 2"x4"s to help dig a 4x2 out of the mud. Didnt check the mileage on either

[tramz]

I went from a '97 4x2 reg. cab - 5.0L, to a '00 4x4 ext cab - 4.8L, now in a '05 4x4 crew cab. The '00 got a little less around town and a wash on the hwy than the '97. The '05 gets the same around town and about 2 mpg better on the hwy than the '97.