Looking at a 2007 Silverado flex fuel truck with 99,000 miles on it. From what I've read ethanol can be harder on engines. The truck's at a dealership and there's no way of knowing if the previous owner or owners ever ran it on ethanol. The price is book, trucks clean and runs good now but I'm thinking the flex fuel makes it a gamble. Agreed?

Disregard, dumb question. There's too many used trucks out there to buy one I've got doubts about.

Vehicles designed for ethanol are in no danger of damage from it. Even better, vehicles designed for E85 run better on E85 than regular unleaded.

The far bigger concern with a '07 Silverado Flex Fuel truck would be determining if it had an oil-burning AFM engine. You'd be out of GM's powertrain warranty, so I'd insist on at least a 3 year/36K mile extended warranty paid by the dealer, and make damned sure it covered the engine.

Like you said, there are way too many other used trucks out there to go wading into that thicket.

FC

^ this. Flex fuel no big deal at all. AFM is.

Depending on where the pickup has been, it may never have even had any E85 fuel in it. I have a 2007 Avalanche and have never once fueled it with E85 because it just wasn't available or cost so much more. It's been a pretty good vehicle as far as the engine goes. Had some sensor problems that have been aggravating. But all in all, not bad for the 145,000 miles I have driven it. Wishing you good luck in your search.

Actually, flex fuel is a plus as you are already geared up to run on E15 or whatever .gov cooks up next. Ethanol messes up when it sits too long or is run through old rubber hoses that deteriorate in its presence.

I have no idea but from little I've read E-85 gets worse mileage than regular gas.

My questions are ...

Is it more cost effective to run E-85 or gasoline?

How many folks with Chevy flex fuel "trucks" run nothing but E-85?

Back to the issue of what truck to buy ... Folically Challenged makes a good point. Chevy trucks of that era are known to have serious problems with oil consumption.

Bingo! Keep us posted.

Of all the things to worry about in a vehicle, this isn't one of them. Ethanol's no problem for a vehicle designed to run on it, and the danger of ethanol in non flex fuel vehicles is way overblown anyway. With the few number of stations that have E85 out there the truck's probably never had it anyway.

I'd be much more worried about it being a GM product than the flex fuel part.

I've only "found" E85 once in the 90K I've had my FlexFuel Yukon, and I wasn't lookin' for it. The truck ran exactly the same with that tank, as any before or after it. It did, however, go about 30% fewer miles on that tank. That just happened to jive exactly with the 30% less I paid per gallon for the E85 vs. 87 Octane.

Maybe I had lower emissions & saved the environment, but I don't like getting only 350 miles out of a 30 gallon tank.

FC

I have only run one tank of E85 thru my 2010 truck. Mileage was way down. As the previous poster said, the mileage was down about the same percentage as the E85 was cheaper than 87 octane.

Don't ever hafta run any &#$% E85 in my new truck. It's already "saving the environment" 'cause it's Rain Forest Green.

So there!