When Does 40 MPG Not Equal 40 MPG?

By Ford Social Member

With the internet, it’s easier than ever to gather information from around the world, but we don’t have to tell you that because you’re reading this via the internet right now! That information doesn’t always come with whole story, though, and one of the stories we’d like to clear up is the difference in fuel economy estimates used in the U.S. and those used in the U.K.

We’ve read your comments, comparing the fuel economy estimates on various Ford products on both sides of the pond, and asking why the U.S. models don’t get the same fuel economy as their U.K. counterparts. The difference is in the yardstick being used to measure the fuel economy.

The first difference is the size of a gallon. In the U.S., a gallon is four quarts. Declaring independence in 1776 excluded the U.S. from adopting the U.K. Weights and Measures Act of 1824, which created the Imperial System of Measurement. An Imperial gallon is 4.8 quarts. That’s a bit of trivia that creates a fuel estimate that’s 20 percent higher in Imperial MPG compared to U.S. MPG.

The next significant difference in the U.S. and U.K. fuel economy estimates is how the vehicles are tested. Monronies, also called window stickers, in the U.S. display the EPA fuel economy estimates for city and highway MPG, as well as a combined number.  There are multiple test cycles used by the EPA to create these fuel economy estimates.

In the European Union (EU), the fuel economy estimates are also made up of several test cycles, with three figures reported: Urban, Extra-urban and combined fuel consumption. That’s where the similarities between the U.S. and the EU tests and fuel economy estimates end.

The specific driving cycles and conditions used to create the EPA and EU fuel economy numbers are quite different, and the fuel economy estimates generated under the EPA system tend to be lower than EU test results for the same vehicle.

So, while it appears that residents of the U.K. get vehicles with better fuel economy, the reality is that it’s just how the estimates are created. If it’s any consolation to U.S. residents, gasoline (or petrol as they call it) in the U.K. is considerably more expensive.
Plymouth Paul 07/05/2011
I am not sure if it is I who triggered this conversation about the UK v. US economy standards or what. I had sent in a comment, on 6-27-11, to Ford and got a response from Marjorie in Customer Service explaining that she had noted my comments and asked that I comment on this forum.

What started the analysis is my memory of the Ford Escort, and Ranger pick-up, that had the Mazda 2.0 diesel engine available in it as an option in the 80’s and the fact that I can currently get a VW Jetta, that gets 45 mpg, the used ones get 50 mpg, with a light diesel in it. I don't remember what the fuel performance was, on the Escort, but I do remember it was much better then the petrol motors at the time. This made me wonder why I can not get a domestic light diesel from Ford, GM, or Chrysler knowing that the Fiesta in Europe probably had a light diesel in it.

Thanks for the education on the Imperial Gallon (I had forgotten about that) – 4.8 quarts, I can remember going to Canada in the 70’s going to watch my older brother play hockey, he was on a travel team, and my dad filling up the station wagon with Imperial Gallons on our way to Kitchener, Ontario, gasoline was less expensive in Canada back then and we use to fill up in Canada.

Doesn’t seem like it would take much for Ford to offer the Turbo Charged Direct Fuel Injected diesel that is offered in Europe, just simply import the engines from the factory in Europe and make them available as an option here. Even if the estimates are 20% higher on fuel volume – imperial gallon, I would bet dollar to dollar the combined fuel economy would be somewhere over 50mpg. The Fiesta is much heaver that the used VW’s that get 50mpg.

It would be an interesting experiment, get a Fiesta diesel from the junk yard in Britain and put it in a Fiesta here and see what happens. The combined fuel economy over there, on the fiesta, is 76.3 mpg, less the 20% difference in fuel volume, that leaves me with 61.04. I am not sure what to subtract for the different testing standards, but I can assure you, with the very same light diesel, the consumer would get significantly better fuel performance.

Just as a side note, the 1998 250 Dodge Ram pick-up truck, with a Cummins diesel, got 25 mpg and that’s a pretty heavy vehicle. I would think the Fiesta would get pretty awesome mpg with the right powertrain.

Thanks !
David Ezarik 07/03/2011
@Brad Krekelberg if it has the diesel, she's about to put petrol in it!
Jamie At Ford 07/01/2011
Hi Michael,
Could you please clarify your comment for me so I can assist? My apologies, but I’m having some difficulty understanding what you mean. Thanks!

Ford Customer Service Division
Jamie At Ford 07/01/2011
Hi David,
If you would like tips for improving fuel economy or to address specific issues you may be having, you can PM me your VIN, dealer name, and approximate mileage. Also, please keep in mind, driving conditions and patterns can affect fuel economy.

Ford Customer Service Division
Dave B. 07/01/2011
Ford is not the one saying what it gets for mileage on the window stickers the EPA is. You can get more or less depending on your driving habits and how much weight your carrying because they are tested by the EPA with only 1 Adult in the vehicle and they are not tested with the A.C. on or anything else that might put a draw on the engine. Every time you step on the brakes it takes a little away so if you ride close to people where you are always going up and down in speed instead of steady as she goes it will kill your mileage. I got over 25mpg on my 1993 Grand Marquis on the highway @ 65mph and I get that same mileage with my Marauder @ 75 mph. You need to find your cars sweet spot where it runs it's best and drive properly then you can get more.
Todd Heide 07/01/2011
Wow look at the Ford haters, Ford must be doing something right to be hated. Rock On Ford! So much better than the rest.
Todd Heide 07/01/2011
my Flex Ecoboost gets 27 MPG Highway! Thanks Ford!
Brad Krekelberg 07/01/2011
Thanks for showing us the 3-door Fiesta we can't buy. I'll bet it even has the turbo diesel and a manual trans. Why not add insult to injury. Haha.
Ron Gosciniak 07/01/2011
My 2011 Mustang gets 24-16 on the freeway at 65 mph with the air on.
Shaun Rutherford 07/01/2011
The United States needs more diesel filling stations and less tax on diesel. That would encourage manufacturers to produce more diesel-powered cars, which are more efficient and can be made cleaner. Diesel is also cheaper to produce, since it is less refined. On Top Gear, Jeremy drove a UK-spec Prius and it got 45mpg, about the same as in the US. I don't know about the difference in measurement.
Mehmet Yılmaz 07/01/2011
2011 Ford Tourneo Connect 110 PS GLX
Susan Walker Edwards 07/01/2011
I think the rest of the world needs to get with Americans!
Kenneth Sherman 07/01/2011
My 2011 Mustang GT 5.0 gets 24 mpg oo the hwy Not bad for 412 hp
Derry O'Dell 06/30/2011
The metric system is in use everywhere except the US burma and Liberia. Time that the Americans get with the rest of the world
Rob Fruth 06/30/2011
My 2010 Fusion hybrid gets `41 MPG city/highway - tnx Ford !
Tim Owens 06/30/2011
All the people on here who say they aren't getting the mpg's they are supposed.... alot of things contribute to your gas mileage. Over or under inflated or out of balanced tires, tune ups, oil changes, etc. You have to take care of any car if you want it to run at its best. Too bad some people just get in and drive and neglect their cars then complain. My 09 Focus gets better mpg's then it advertised because i take care of it.
cole 06/30/2011
The EU generates estimates in litres/100 kilometers or Imperial MPG, which is used in the U.K.


Cole Quinnell
Editorial Director
Larry Adams 06/30/2011
My 06 Fusion V6 window sticker shows 29 MPG highway---I have been getting 33 MPG highway at stay with the traffic speeds too!!
Larry Adams 06/30/2011
Does the EU use kilometers instead of miles as well as liter verus gallon?
Raul Albor 06/30/2011
92 ford thunderbird 3.8 factory supercharged get 20 mpgs when I drives slow but I can burn the whole tank in about 200 miles if I wanted too!! That equals about 12 mpgs!!!
Dena McLean 06/30/2011
When my husband is driving! Or when I have 200lbs of horse feed in my trunk.
David Rutherford 06/30/2011
When Ford tells you your car gets 41 city count on 36 when they tell you 36 count on 34 for highway. And no I don't drive fast just speed limit and don't accelerate too fast.
Andrew D Dziatkewich 06/30/2011
And my escape V6 gets 10 liters per 100km in the city, which for you uncivilized non-metric folk is close to 23 mpg. Can't really complain there.
Michael Bashta 06/30/2011
Oh! That clears up a lot!
Bryan Fromal 06/30/2011
My V8 F150 4x4 gets 23 mpg highway. You can't try to go 0-60 in 3 seconds and still expect to get good gas mileage.
Vince Zalamea 06/30/2011
When you need to drive like grandma with the "SFE" package with butt-ugly wheel covers on low rolling resistance tires. in other words, it's possible but probably won't be a lot of fun.
Jacob A. Weinstein 06/30/2011
@jesse ford aint goin anywhere so get used to it.
Ryan Fugitt 06/30/2011
When its 39mpg
David Fige 06/30/2011
My 3.0 lire V-6 Ranger reg cab with 150 HP gets 20 MPG highway on it's best day from new. Just wish Ford would sell those small deisel for the small pick ups like in other countries. I don't need to pull the world, just a mower and my kayaks. You would sell millions of them.
Dean Baldwin 06/30/2011
Petrol in uk £1.36/litre, think you Americans get a bargain. :)
Brian Oh 06/30/2011
the answer is "when u drive a ford" my lincoln mks gets nowhere near the mg ford says ill get
Christopher Spielvogel 06/30/2011
When a car rated 40 but the driver isn't trained how to drive a 40 mpg car
Dennis Stimson 06/30/2011
liters baby:0
Matt Zizzo 06/30/2011
When my cummins says it gets 22mpg and it really means 22mpg. Lol