Is there any reason to Not continuing to use E85?
Not really. It allows the engine to make more horsepower and torque and if the cost is low enough, can be less expensive to run. It certainly burns cleaner too. I've seen no ill effects with the truck sitting in the driveway for 1-2 weeks with a 1/4 tank of E85 on board. Until recently, that was often the norm.
Now for the kicker, I've just completed my 12th tank of E30. E30 costs less than 87 octane and delivers more mpgs than 93 octane gasoline in my truck. If E30 isn't available you can make your own. Soon as the light comes on pump in 5 gallons of E85 and 17 of gasoline for those of you with the short trucks. This will give yield an alcohol content of around 20-22% and the octane rating will be 91 if you use 87. If you pump in 93, it will jump to 95.
If you have a 31 gallon tank and wait for the light, pump in 6 gallons of E85 and 20 of gasoline. If you're starting out with a higher alcohol content you can get the R+M octane rating up to 96 with these mixes.
For those trying this for the first time, you can't just fill up once and expect the full benefits, you've got to give the motor AND transmission time to adjust and it usually tanks at least 2 tanks and usually 4 or 5.
If you're running around town any form of E85 is great but for long trips you want the range and availability which isn't as easy as just picking any exit as a desire to run long distances on Ethanol requires thorough planning to identify stations that carry it and will be open when you pass through.
I could get from the Treasure Coast to Houston, Texas now on E85 if I wanted. But man, this E30 is even better for endurance while still burning clean through the motor.
