We've written quite a lot about the gas mileage of Ford's two new 2013 hybrid models, the C-Max and Fusion hybrids.

That's because a lot of shoppers and buyers have been talking about it.

Both cars are rated at 47 mpg combined, and neither car seems to achieve anything close to that rating in varied real-world usage.

Our own latest test of a 2013 Fusion Hybrid, for instance, covered two days and 244 miles and resulted in a fuel-economy reading of 36.8 mpg.

Our test routine, however, is to drive all our cars on a consistent route as we would use them in real life.

That lets us compare different cars to each other, and over time, we've found that our results tally quite closely to owner experiences--if not always EPA ratings.

Now another outlet has brought more rigor to testing the Ford C-Max Hybrid against its closest competitor, the Toyota Prius V wagon (it also included a Prius liftback in its test).

The CleanMPG site (known for its active forums and a strong propensity toward extreme hypermiling) looked specifically at Ford's advertising claim that the C-Max Hybrid gets better gas mileage than the Prius V.

Based on EPA ratings--the only numbers automakers are legally allowed to advertise--that's true. The C-Max is rated at 47 mpg combined, the Prius V at 42 mpg combined.

The article itself is very long, with explanations of the methodology used, route and elevation maps, lots of data to dig into, and photos, maps, and graphs galore.

We recommend that you read the whole piece, titled Ford's 47 mpg City/Highway/Combined Hybrid Ratings Ring Hollow, to understand the thoroughness of the test...but stop reading this piece here if you don't want to hear the bottom line.

Consider this your spoiler alert.


2012 Toyota Prius V hybrid wagon, test drive in Catskill Mountains, Jan 2012

2012 Toyota Prius V hybrid wagon, test drive in Catskill Mountains, Jan 2012

At the end of CleanMPG's lengthy and detailed test, the observed city driving results for the Ford C-Max delivered 52.0 mpg (against its rated 47 mpg) while the Toyota Prius V logged 55.8 mpg (versus a rating of 44 mpg).

On the highway, the Ford C-Max delivered 35.5 mpg (versus its rated 47 mpg) while the Toyota Prius V came in at 40.8 mpg (against its rated 40 mpg).

In both cases, the Prius V did better against its ratings than the C-Max Hybrid.

That squares with our observation that Toyota Prius models deliver real-world mileage much closer to their EPA ratings than the two new Ford hybrids.

The Priuses have less powerful engines and smaller electric motors, meaning that they're likely more stressed on the unrealistic EPA test cycles than the Ford hybrids.

Or, put another way, the Ford hybrids do much better on the relatively gentle EPA testing runs than they do in real-world driving--when drivers will sometimes (or often) use all the power available under their right foot.

This hasn't stopped Ford from continuing to trumpet the superior EPA ratings. As the site concludes,

Ford’s claims of the C-Max's superiority in city, highway and combined fuel economy over the Prius v per its EPA ratings in press releases and advertisements continue even with the number of counter claims provided by journalists, automobile reviewers, and anecdotal comparison evidence by some very important automotive media outlets.

In any event, we tip our hat to CleanMPG for providing another data point in the discussion of Ford's real-world gas mileage for its C-Max and Fusion hybrid models.

ow serious a problem do you think the Ford hybrid discrepancies are? Does the difference between, say, 37 mpg and 47 mpg in actual driving really affect buyers?

Or are the cars good enough--and still more efficient than non-hybrid competitors in their class--that it won't really matter much?

Leave us your thoughts in the Comments below.


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