2013 Ford C-Max Hybrid
2013 Ford C-Max Hybrid (Ford Motor Company)

Ford will begin offering a free software update in August to improve the fuel economy of the 2013 Ford C-Max Hybrid, 2013 Ford Fusion Hybrid and 2013 Lincoln MKZ Hybrid.

Ford says the software update will improve its hybrids’ real-world fuel economy. “We believe these actions will provide our customers enhanced on-road fuel economy satisfaction,” says Raj Nair, group vice president of global product development at Ford, in a press release.

According to Ford, the software update will increase the electric-only top speed from 62 to 85 mph, reduce engine warm-up time, decrease aerodynamic drag using Ford’s active grille shutters, reduce engine cooling fan speed and optimize the climate control system.

“Customers should see the most improvement at highway speeds, during air conditioner use and operation in colder climates,” says Nair. He expects the mileage improvements to vary based on the way people drive. “Just as individual mileage can vary based on driving styles and environmental conditions,” he says, “we expect fuel economy improvements will differ from customer to customer depending on individual driving habits.”

Ford’s announcement Tuesday comes amid criticism that the company has inflated the fuel economy numbers of hybrids like the 2013 Ford C-Max Hybrid. Reuters reports that “Ford faces a number of class action lawsuits that claim the No. 2 U.S. automaker overstated the gas mileage on its hybrids.”

According to Business Insider, one plaintiff, who owns a C-Max Hybrid, averaged aproximately 37 mpg in combined driving, which is less than the EPA's 47 mpg combined estimate. 

Consumer Reports tested the car last year and also reported 37 mpg combined.

Like other automakers, Ford uses the EPA's fuel economy estimates in its advertising. Organizations such as Consumer Reports have recently questioned the EPA’s testing methods, saying that the EPA’s tests don’t reflect real world driving and can result in inflated fuel economy numbers, especially for hybrids. The EPA last addressed concerns about its fuel economy tests in 2008, when it changed its methods to better reflect real world driving. It included faster acceleration, air conditioner use and colder outside temperatures in its tests, and average fuel economy numbers dropped.

Autoweek reports that the software updates should take a half day, and that Ford encourages 2013 hybrid owners to make an appointment with their dealer.

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