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The Consumer Guide to E85 Ethanol Vehicles

        Auto | Fuel-efficient Vehicles

The Pros of Buying an E85 Ethanol Vehicle
E85 ethanol flex-fuel vehicles have been available for years, but choices are broader than ever for 2007, with 27 different models for sale in the U.S. That's up from 20 for the 2006 model year, and just seven in 2000. GM offers 15 E85 ethanol flex-fuel models totaling about 400,000 vehicles. It offered nine models in 2006. Ford expects to sell 250,000 E85 ethanol flex fuel models this year. Clearly, E85 vehicles are growing in popularity and you might be asking yourself, "What's in it for me?"

E85 Vehicles Are Simple

GM identifies its E85 ethanol flex-fuel vehicles with "Flex Fuel E85" badges and yellow fuel-filler caps. Ford labels its E85 ethanol flex-fuel models with a tree-and-road logo and a decal reading "FFV," for Flexible Fuel Vehicle. The Chryslers, Dodges, and Jeeps display a silver "Flex Fuel E85" tag. E85 ethanol flex-fuel vehicles from Mercedes-Benz and Nissan do not carry any special identification.

E85 fuel door sticker

yellow gas cap

The sticker on the fuel door (top) will let you know if your car or truck is E85
compatible. A yellow gas cap can be found on most General Motors'
E85-compatible vehicles (bottom) and indicates the same.

The surest ways to determine whether you may already have an E85 ethanol flex fuel vehicle is to consult your owner's manual or check for an identifying sticker inside the fuel door. A list of E85 ethanol flex fuel-compatible vehicles is also available from several Web sites, including and

Though some estimates say it costs the manufacturer about $150 to make a vehicle E85-ethanol capable, no automaker charges extra for an E85 ethanol flex-fuel vehicle compared to its gasoline-only counterpart. Some flex fuel versions of engines are optional at extra cost, but it's the same charge as for the conventional gas version of the same engine. The Ford F-150 pickup is an example. Its base price is $18,220, but that's with a 202-horsepower 4.2-liter V6 engine, which runs only on conventional gasoline. To get E85 ethanol flex-fuel capability, you have to order the 300-horsepower 5.4-liter V8. The flex-fuel-capable V8 is a $1,645 option, but that's the same price as its gasoline-only counterpart.

E85 Is Just as Good as Gasoline

If you purchase an E85 ethanol flex-fuel vehicle, or discover you already have one, and choose to run it on E85 ethanol it won't require drastic changes in your driving habits. Any E85 ethanol flex-fuel vehicle can run on 100 percent E85 ethanol, 100 percent pump gasoline, or any combination of E85 ethanol and gasoline. The vehicle's on-board diagnostic systems adjust for any of these blends and keep it running according to manufacturer's specifications.

Neither should you notice a difference in vehicle performance using E85 ethanol compared to gasoline. E85 ethanol flex-fuel capability doesn't change the horsepower ratings of any of these engines. Their "flex fuel" capability means they have to run well on either type of fuel, so even though E85 ethanol carries an octane rating of 100-105, versus 85-95 for gasoline, manufacturers do not tune E85 ethanol-capable engines for higher performance than their gas-only counterparts.

Indeed, in a road test of an E85 ethanol flex-fuel Chevrolet Impala on both 87-octane gasoline and E85 ethanol, Consumer Guide's automotive editors could not detect a difference in engine performance, smoothness, or sound.

Some E85 ethanol proponents say the blend keeps fuel systems cleaner than gasoline, for potentially lower long-term maintenance costs. But GM and Ford have no special maintenance requirements for their E85 ethanol flex-fuel vehicles, but other manufacturers may require use of specific engine lubricants. Check your owner's manual or consult with your dealer. And if you're fueling up with E85 ethanol, share that fact with your dealer service department or parts supplier when ordering replacement parts.

E85 Vehicles Are Eco-Friendly

If your concerns run to America's energy independence and the environment, an E85 ethanol flex-fuel vehicle is one way to express it. Every mile you drive on E85 ethanol fuel is a mile you're not driving on conventional gasoline, and that prolongs the plant's stores of petroleum.

Vehicles fueled with E85 ethanol have lower carbon monoxide and carbon dioxide emissions than conventional gasoline or diesel vehicles, according to the U.S. Department of Energy. In addition, ethanol is water soluble, non toxic, and biodegradable. E85 ethanol also contains far fewer potential contaminants than found in gasoline.

While these advantages are considerable, there are some drawbacks to E85 vehicles that you should keep in mind. We'll look at some of the negatives in the next section.