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I have a 2006 GMC Sierra pickup. Since I started using E85 gas, mileage has dropped drastically. Can you tell me if I need to ues a different type of spark plug? Thanks, Will

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These trucks with the flex fuel systems will not get as good of milage on E85. They are designed this way. I haven't heard of any kind of spark plug that will help you in this. It is kind of a trade off, better milage but gas is more expensive, E85 is cheaper and more enviromently freindly but gas milage suffers. I also have a 2006 Chevy but did not get the flex fuel for this reason. On my car I use it and the milage suffers a little but with the trucks you will see even less milage due to the fact that trucks get worse milage than cars to begin with.

Posted on Nov 15, 2010


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