Don’t Expect Ford Hybrid MPG Dispute to Slow Sales

Peter Foley | Bloomberg | Getty Images

Alan Mulally, president and chief executive officer of Ford Motor Co., speaks during the unveiling of the Ford Fusion in New York, U.S., on Tuesday, Sept. 18, 2012.

Ford CEO Alan Mulally has said it himself: Fuel economy is the number one factor for people when deciding what car to buy. Just a few days after Mulally made that claim while making the rounds on morning TV shows, the miles per gallon (mpg) ratings of two Ford hybrid models are being questioned.

Consumer Reports says it tested both the Ford Fusion Hybrid and the Ford C-Max Hybrid and found both models got 8-10 miles per gallon less than the automaker promises.

Ford and the EPA say both models get 47 mpg. Consumer Reports says the Fusion Hybrid gets 39 mpg (city/highway combined) while the Ford C-Max Hybrid gets 37 mpg (city/highway combined).

In explaining its results, Consumer Reports wrote, "Yes, the disclaimer on EPA fuel-economy labels notes that 'your results may differ.' But the overall mpg for these C-Max and Fusion models is off by a whopping 10 and 8 mpg, respectively, or about 20 percent."

Ford Stands By MPG Claims

Ford disputes the Consumer Reports claims about the Fusion and C-Max Hybrids. In a statement, the company said, "Early C-MAX Hybrid and Fusion Hybrid customers praise the vehicles and report a range of fuel economy figures, including some reports above 47 mpg.

This reinforces the fact that driving styles, driving conditions, and other factors can cause mileage to vary. For those customers who are more focused on optimizing their fuel economy, Ford's new hybrid SmartGauge with EcoGuide eco-coaching technology features even more ways — such as Brake Coach and an "Empower" gauge for more efficient stopping and acceleration — to help our customers achieve higher mileage."

To be clear, the stickers on the Fusion Hybrid and C-Max Hybrid contain the same disclaimer you'll find on every new car. The mileage you get in real world driving could differ from what is on the sticker.

Still, it is natural to wonder if the Consumer Reports claims will ultimately lead to Ford changing the mpg ratings on two of its popular hybrids. Nobody is saying that will happen, but just last month Hyundai had to lower its fuel economy ratings for several popular models after an EPA investigation.

Don't Expect Ford Sales to Fall

Both the Fusion Hybrid and the C-Max Hybrid are building momentum in a market dominated by the Toyota Prius Line-up. Ford has sold 10,856 Fusion Hybrids this year and 8,999 C-Max Hybrids.

Those pale compared to Prius sales of 216,619 according to the research firm AutoData. So how much could this dispute hurt hybrid sales at Ford? In my opinion it's not likely to have a big impact.

(Read More: Cars With the Best Resale Value.)

I base that opinion on the reaction to the Hyundai having to lower the fuel economy claims of several models including the red-hot Elantra. In the auto world it was a big story. In the real world it did little to dent sales. In fact, last month Hyundai grew sales by 4.7 percent. In 2012, Hyundai has set a new record for U.S. sales (643,572) and it still has one month left to increase those record results.

Car buyers do care about mileage. Yes, some may decide not to buy the Fusion and C-Max hybrid because the Consumer Reports claims, but I think most who are interested in these models will still buy them.

The Hyundai case shows that Americans will still buy cars even if the mileage stated may not be exactly what they get out on the road. Especially since Consumer Reports found both the Fusion and C-Max registered very good fuel economy.

—By CNBC's Phil LeBeau; Follow him on Twitter @LeBeauCarNews

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