What a 2,000-mile Ford C-Max Hybrid road trip reveals about its missing mileage

For the last two weeks of 2012, my family drove a Ford C-Max Hybrid. We took it on freeways and on country roads, into big cities and through pine forests. At times, it was full of luggage and food, and other times, it contained nothing but our oversized winter coats and us. It ventured through rain and snow, freezing cold and warm winter days. It went up steep hills and through mountain passes, and experienced equally aggressive drops. Though we never veered off paved roads, we still drove the crap out of that car. We saw most of the South in our C-Max. Even Arkansas.

When the C-Max debuted last year, promising 47 mpg city, 47 highway, 47 total, and a name that sounds like a shoddy nutritional supplement, it was dismissed as almost too good to be true. And it was.

Once the pros, not to mention the customers, got their hands on the C-Max steering wheels, those claims turned out to be as false as Castro’s teeth. Consumer Reports, the most objective source imaginable, couldn’t get the C-Max’s mileage over 38. Online boards began to fill with angry posts from drivers who were seeing numbers like 35 and 36. In December, a California law firm filed a class-action suit against Ford, speared by a guy who was pissed off about his C-Max's 37 average. I just had to try it for myself.

While I’ve never claimed to be a great driver, or even a particularly good one, I do know something about hybrids. We’ve been a Prius-driving family since 2006, and have gotten used to the concept of gliding to save a dollar. It’s been a long time since I’ve gotten fewer than 44 mpg on my daily driver, and just as long since I’ve had to fill up more than a couple of times a month.

The Prius V, which the C-Max is targeting directly, reliably gets 42 mpg. By comparison, the C-Max is pure mendacity. I saw the MPG video-game meter in the left corner of the dash display hit 47 once, the first time I took it to pick my son up at school, a ten-minute drive, almost entirely downhill, which I did with the windows open and my foot almost entirely off the gas pedal. After that, I drove it around town, in warm weather, for a couple of days and watched the numbers gradually drop, finally settling in the 36-37 range. Then we took it on our annual holiday death-march to visit my mother-in-law in Nashville.

After the first two hours of the trip, we were feeling somewhat optimistic.

The C-Max is a little hatchback, but it has a deceptive amount of storage. We were able to fit three suitcases, a big box of presents, a few random bags of stuff, a child, and a small dog, and we were still all able to breathe inside. It boasts a decent amount of zip and maneuverability, and all the modern plug-ins and doo-dads that you expect from a $30,000 hybrid, everything, that is, except for gas mileage.

To be fair, we drove it into the heart of winter, and thus needed to use the heater, and the window defroster, and sometimes the seat warmers, which were so hot, even at the lowest knob turn, that they made us sweat. At the highest setting, I imagine, they could broil a chicken. We also drained battery power using an electric adapter, which we plugged into a cigarette lighter so we could keep a smartphone and a portable DVD player powered. Even with all that, the electric part of the hybrid drive train never dipped below half-charge. There was plenty of juice in the maker; I know all about the magic of regenerative braking.

After the first two hours of the trip, the mpg counter read 38.6, and we were feeling somewhat optimistic. Somewhere south of Dallas, the numbers began to plunge, and they never quite recovered. For hours, they hovered in the 36 range, but by the time we got to Tennessee, we were at 35.9, never to see the upper tier of the 30s again.

Toward the end of our holiday trip, on the dreary voyage back, we filled up somewhere around Texarkana. If the C-Max had gotten 47 mpg, like Ford claimed, that would have taken us to Austin with more than a quarter of a tank to spare. But 40 miles from home, the yellow warning light for low fuel turned on. I was tired of driving and didn’t want to fill up again.

“Screw it,” I said. “We’re doing this.”

With ten miles left, we turned off the heat. We coasted, on flat roads, going barely 50 miles per hour. At that point our total mpg was already shot, but we were just trying to get home without disaster. Even at that circumspect moment, the mileage indicator showed that we were around 40, usually dipping below. No amount of care could save my efficiency. We got home with maybe 14 miles of gas left in the tank, disaster barely averted.

These are odd days for gas mileage calculations, with new government standards forcing automakers into contortions, causing seven-day-week all-nights in engineering departments from Detroit to Seoul. So it’s understandable why Ford would tout a 47-mpg car, and I’m sure that on some test machine or track, under ideal conditions, driven just the right way, the C-Max has achieved that number. But consumers can’t drive cars like they’re china dolls. Sometimes we need to go up a hill or press on the gas. Miles per gallon needs to be more than a utopian ideal.

Over more than 2,000 miles in the C-Max, which seems like a very reasonable sample size, we averaged 33.5 mpg. When it came time to go to the store the next day, we put it into dry dock and took our unexceptional Prius out instead. We gauged the mileage. It got 46.3. And we didn’t even have to try.