Even though gasoline containing upward of 15% ethanol content (E15) hasn’t come on the consumer market, the government has already finalized the labels that will be affixed to pumps carrying the fuel, a sign of E15 will likely make it to your local gas station at some point. Now Bloomberg reports that nine automakers, including GM, Chrysler and Toyota have warned regulators that putting E15 in your tank may void your vehicle’s warranty.

“While Chrysler has been a strong advocate of renewable fuels, we have concerns about the potential harmful effects of E15 in engines and fuel systems that were not designed for use of that fuel,” Chrysler’s senior vice president of external affairs, wrote in a letter to Wisconsin Congressman James Sensenbrenner, vice chairman of the House Committee on Science, Space and Technology.

The E15 label released last week by the Environmental Protection Agency alerts consumers that the gas should only be used in vehicles with model year 2001 or later and that it may do damage — and is prohibited to use — in “other vehicles, boats and gas-powered equipment.”

Following the label’s release, the Alliance of Automobile Manufacturers, claimed that it doesn’t provide sufficient information to consumers. A rep for the group told the NY Times that the label should tell drivers to check their owners’ manuals when deciding which fuel would be best suited to use in their vehicles.

Ford, Carmakers Criticize EPA’s Ethanol-Blend Proposal on Warranty Concern [Bloomberg]

E.P.A.’s E15 Pump Labels Raise Ire of Automakers [NY Times]

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