has anyone tried E85? I know the MPG goes down but performance is better and price is way better. Just wondering. I have 06 4.4 and have always ran premium.

 

Several points; The manufacturer "recommends" premium instead of requires because the vehicle will operate on regular fuel, just not optimally. It will probably operate on paint thinner too.
While the computer will compensate for the differant AKI of the fuel, it does so by varying the ignition timing which directly relates to power and operating temperature. Retard timing = higher temps.
E85 = 85% Ethanol. Do not use this in any vehicle that is not marked "Flexible Fuel". Ethanol is corrosive and will deteriorate fuel system components that are not designed for it. In fact, don't use anything over 10% Ethanol.

 

When I first got mine I was getting 11-12 city and 17-18 highway. I ran BG44K, and cleaned my MAF which was black. However, saw no difference. I then changed my transmission oil and filter which was also black, and gained 2 mpg in both.