gooffeyguy
Tom
Figure it out as cost per mile. When you have the 6.2l and have to run premium fuel, the E85 (which is about 105 octane) when over $1 per gallon cheaper but you get 2-3mpg less, may actually be cheaper to run.From everything I have read online flex fuel isn't worth it from a cost perspective unless you have a performance setup that actually can use the extra octane and cooling effects of ethanol. Most all street driven ls engines don't. Your mileage will drop enough that the cheaper fuel becomes more expensive and there is no performance gain for our low compression engines.
Now if you have the 5.3l and run regular unleaded, the less than $0.50 gallon difference it costs isn't worth it.