Consumer Reports Questions Ford's Fuel Economy Ratings Consumer Reports said on Thursday that its tests showed the 2013 Ford Fusion Hybrid and C-Max Hybrid fall short of the estimated fuel economy numbers assigned by the Environmental Protection Agency. The E.P.A. figures that appear on the window labels of both Ford vehicles are 47-m.p.g. city, 47 highway and 47 combined. In the Consumer Reports tests, the Fusion Hybrid delivered 39 m.p.g. combined, while the C-Max Hybrid SE came in at 37 m.p.g. over all. The organization said the discrepancies between its test results and the E.P.A. figures were the largest it had seen among current models. While the fuel economy numbers that appear on the window labels of new vehicles are published by the E.P.A., along with a disclaimer saying "your results may differ," most E.P.A.-estimated numbers are determined by the automobile manufacturers in dynamometer tests that simulate a prescribed driving sequence. E.P.A. spot checks about 15 percent of the new car fleet in its own test labs. "Early C-Max Hybrid and Fusion Hybrid customers praise the vehicles and report a range of economy figures, including some reports above 47 m.p.g.," Ford said in a statement in response to the Consumer Reports test results. This reinforces the fact that driving style, driving conditions and other factors can cause mileage to vary. Wesley Sherwood, a Ford spokesman, said Ford maintains a forum for C-Max owners where they can comment on their fuel economy. Some who have posted there have done no better than the Consumer Reports tests, while others have been able to achieve close to or better than the E.P.A. estimates. The Consumer Reports challenge to Ford's fuel-economy numbers comes after Hyundai and Kia had to reimburse consumers for overstating the fuel economy of some of their vehicles. The E.P.A. uncovered those discrepancies when it investigated Hyundai and Kia mileage numbers after numerous complaints from consumers. The automaker subsequently admitted to having produced inaccurate numbers. Consumer Reports, however, praised the fuel economy of the Hyundai Elantra in its tests of that vehicle, although the Elantra was among those cited by the E.P.A. In a video review, Tom Mutchler, a Consumer Reports automotive engineer, said the Elantra "gets very impressive fuel economy. We got nearly 40 m.p.g. on the highway in our tests. In a test of the Hyundai Sonata Hybrid, another vehicle cited by the E.P.A., Mr. Mutchler criticized the car's on-road behavior, braking and handling, but praised its fuel economy. Jake Fisher, director of auto testing for Consumer Reports, when asked in a telephone interview about the organization's Hyundai results, said that although Hyundai and Kia had admitted that its window-label fuel-economy numbers were inaccurate, the Elantra and Sonata Hybrid achieved mileage figures close to the originally published numbers in Consumer Reports testing and in subsequent E.P.A. tests. He added that the organization has not accused Ford of falsifying test results and said that the 47 m.p.g. fuel economy numbers may well be what an accurately performed E.P.A.-cycle test revealed, but they could not be achieved in the Consumer Reports tests. In reporting on the fuel-economy discrepancy of the Ford vehicles, Consumer Reports said that it had not yet concluded testing of the Ford Fusion and C-Max hybrids, but offered some initial praise of the vehicles, saying Fusion "is a solid well-rounded package, while C-Max is "a very practical package that also drives well. They further noted that the mileage achieved by the Fusion Hybrid and the C-Max Hybrid in their tests, while far less than the E.P.A.-estimated figures, was nevertheless very good, with Fusion's 39 m.p.g. being the best of any family sedan tested, and C-Max placing second in its class, bettered only by the Prius V.