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Converting awd to fwd

Hello out there. I have a 2007 Ford Escape Limited with AWD. I get a constant 18.2 mpg and wonder (since I really have no need for awd) if converting it to fwd to get 5 mpg better is possible, and whether that is simply a mechanical disconnection or there are computer boards, etc. that would have to be replaced/reprogrmmed. Dave.

I’m pretty sure this isn’t possible, and here’s why. We always talk on here about how, on AWD vehicles, the tires must all be exactly the same diameter or damage to the driveline (specifically, the center differential) can occur. Because of this, whenever an AWD vehicle needs just one tire replaced, much of the time you either have to replace all four tires, or have the new one shaved down to match the three existing ones.

Now try to imagine what would happen if you simply removed the driveshaft to the rear wheels (essentially the same thing as those two wheels not rotating at all) while the front wheels do all the work. I have to believe this will very quickly toast the driveline.

That said, I’m only guessing and I’ve never seriously looked into something like this. Perhaps one of the longer-tenured members here can confirm or deny my assessment?

fwd versions usually only get 1 mpg better - why do you think 5? And the improvement comes partly from the lighter weight, so this isn’t something you want to do. Little gain, lots of trouble.

You’d be better off in the long run to just trade it in for a FWD version. If you just remove the drive-shaft, you’re still carrying that extra weight on the vehicle, so nothing will really be gained by it.

Appreciate the comments, guys, and you’re making some sense, though I’m not quite sure of the center differential issue. To those of you arguing that I won’t get a mileage improvement, then why do FWD’s get city/highway different mileage while AWD’s get the same mileage all the time. If it was just a matter of the weight of the drive shaft, then I would get better highway highway mileage by removing it, right?

Does your escape have a “lock” button you can push to lock the center differential? If not, then removing the rear driveshaft will immobilize the vehicle.

Modifying your vehicle is NOT a practical idea…

If you want a FWD Escape trade your AWD Escape for one with FDW. Modifying the vehicle is a bad idea, and probably won’t gain you any fuel mileage.

Curb weight awd: 3464 lbs
gross weight AWD: 4520 lbs
MPG: 17/21/19

curb weight FWD: 3298 (166lbs lighter)
gross weight fwd: 4380 (140 lbs lighter)
MPG: 18/23/20 (1/2/1 MPG better)

You’ve got the weight of the center and rear differential, plus all the energy required to move those extra parts. And, as you can see, there’s only a couple MPG difference between the 2, which could be negated by careful driving habits.
If fuel mileage is your only concern, then trade your SUV in for a more fuel efficient sedan or coupe

“why do FWD’s get city/highway different mileage while AWD’s get the same mileage all the time”

Not only is that statement invalid, I have never even heard anyone utter that information previously.
If you look at the EPA gas mileage figures for any AWD vehicle, you will see different gas mileage for their city driving cycle vs their highway driving cycle, with the highway figure better than the urban figure.

Based on my experience with two AWD vehicles, while they are not quite as fuel-efficient as I would like, they both consistently achieve about 4 mpg better fuel economy in strictly highway driving.

If your Escape achieves the exact same gas mileage in highway driving as it does in urban driving, something is wrong.

We went from the “mini van” craze to the era of SUV’s as the auto fad of the moment. Dave, like many others bought an SUV with AWD or 4WD and never really uses or needs these features. Part of the mpg loss with an AWD or 4WD is simply the extra weight of the parts that drive the 2 additional wheels. FWD or RWD cars and trucks don’t need central differentials, tranfer cases, and a 2nd drive shaft, and a 2nd differential.

The next loss of mpg is the friction loss of keeping all these parts moving. Depending on the type of drive system some have more inherent friction than others. If it is possible to disconnect the extra drive wheels the only saving in mpg would be reduced friction. The 1-3 mpg gallon savings must be balanced against the possible negative consequences of running the car “disconnected”.

The early Jeeps had “lock out” hubs on the front wheels which you manually turned to engage or disengage. When you disengaged them the axles and front differentail didn’t rotate. To reduce friction you’d have to figure out how to disengage the AWD or 4WD systems at the wheels. If you can’t the axles and differential still spin and your friction losses continue with virtually no change in mpg.

Short answer, don’t do it. Next time you get a car or truck don’t buy it with AWD or 4WD.

It would cost more than you could ever save in gasoline. Even trading it for a FWD Escape does not make much sense to me. Enjoy your Escape for now, ad get something else when you get a new car or truck in a few years. If you drive 15,000 miles per year, you will save $250 at $3/gallon by switching to a FWD Escape.

If you didn’t need AWD why did you get it in the first place? 18.2 MPG isn’t bad, my SUV struggles to get 10 MPG around town. Anyway as others have pointed out, there’s no real “good” way to covert it over to 2WD and even if you did an extra 5 MPG would be a pipe dream.

Okay, gents. I get the picture. Case closed.

I bought the vehicle because I wanted an Escape, and this one was a fully-loaded Limited model and was a monster bargain (used). I easily bought it for 10,000 less than a new one. All three dogs fit comfortably behind the rear seat, and the vehicle acts like a truck and drives like a car. My ONLY peeve is the 18.2 mileage, and yes it is ALL THE TIME, or at least that’s what the computer readout says. Perhaps my mileage computer doesn’t compute.

Thanks for your input, guys. It has been valuable even if a bit sarastic here and there. I have been appropriately counseled and shall be more thankful for my 18.2.

Dave

Yes, I suspect that your mpg computer is inaccurate–as are most of them.
I would suggest that you use the tried and true method of using a calculator to divide miles driven by the amount of gas it takes to fill the tank. That will give you a far more accurate reading.

And, if you do find that your highway gas mileage and your city gas mileage are exactly the same, then there is something wrong. One possibility is that your tranmission might not be shifting into overdrive at highway speeds. That could produce highway gas mileage that is very similar to city gas mileage.