Criticism over discrepancies between their official EPA estimates and actual on-road fuel economy notwithstanding, sales of Ford's ever-expanding hybrid/electrified-vehicle fleet have been on an impressive upswing. During the first half of 2013, those greener machines grabbed nearly 16 percent of the total segment here in the U.S. -- a 12-point year-over-year gain. In a move aimed at ensuring that momentum continues -- and at bolstering owner satisfaction levels -- the automaker has announced an updating effort designed to improve the real-world mileage of the 2013 Ford C-Max Hybrid, 2013 Ford Fusion Hybrid and 2013 Lincoln MKZ Hybrid.

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According to Raj Nair, group vice president, Global Product Development, this software-based calibration revamp that begins in August will manifest itself in several areas, all geared toward providing current and future owners of those models with "enhanced on-road fuel economy satisfaction." Key changes include increasing their maximum EV-only speed from 62 to 85 mph, expanding the use of drag-reducing Active Grille Shutters over a wider range of operating conditions, reducing fan speed as a function of coolant temperature, further optimizing the climate control system to trim energy use, and shortening engine warm-up time by 50 percent to allow earlier shutdown at stops even more quickly after a cold start.

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In addition to making software changes on subsequent C-Max Hybrid, Fusion Hybrid and MKZ Hybrid models as they roll down the assembly line, owners of some 77,000 eligible vehicles currently on the road in the U.S. and Canada will be notified by Ford to bring them to a local dealer to have the same upgrading performed at no charge. A spokesperson for the company indicated that the process should take no more than a half day to complete.

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

Other Hybrid Vehicle News...

Toyota and Lexus hybrid sales have now topped 5 million worldwide 

The 2013 VW Jetta Hybrid gives the automaker seven cars with 40+ mpg 

The 2013 Ford C-MAX Energi is the EPA's most fuel-efficient plug-in hybrid