E 85 Fuel

I have a 2003 Silverado and was wondering if I can Run E 85 gas without making any changes to the engine. Any one run this fuel, how does the truck run?

You can run E-85 without making any changes if you have the VIN code Z flex-fuel compatible 5.3L V8.

The key to E-85 is supposed to be cheaper cost and environment. However - the cost per gallon isn't the final measurement. A gallon of E-85 does not produce the same level of energy as a gallon of regular unleaded gasoline - in fact - most tests done on it and most comments made by gas station providers of the product claim that you will get about 12% to 20% less results than you do with normal gasoline. Sooooooooo ......... is it any cheaper? Math will say it isn't. How about wear and tear on the engine? Everybody has to judge for themselves.