Originally Posted by
alamedaguy
Our LAS Wild Card turned out to be a Grand Marquis. It guzzled gas, but used E85 (of which I had never heard) so at least it was a little cheaper. Although that may have contributed to the poor mileage, I guess.
E85 is an ethanol-based fuel replacement. Engines with the E85 sticker are dual-mode and can run both on E85 or regular gasoline. You do not
need to use E85; it is optional.
E85 has less potential energy than an equivalent volume of gasoline, but as you indicated, it is usually a bit cheaper than gas, so it comes out about even.