There is another aspect to the real cost of E85: My Tundra requires 8 qts of 0w20 full synthetic. Recommended oil change intervals are 5000 mi. Unless, you use E85, then it becomes 2500 miles.!
Let's see, 8 qts at around $8 per qt, $64 in added expense in 2500 miles. E85 is rated in that truck at 13 MPG, E10 at 17.
There's no way mine will ever see any E85!
Wow, that too bad that Toyota built and engine that couldn't take it. I regularly go out to around 10% left on the oil life monitor on my Silverado, which equates to around 7500 miles, give or take, on oil changes using E85. There is no special oil change interval recommended by the OEM, and the oil samples look fine. I might not even do them, but my oil supplier provides free oil sample kits with free analysis, so it just makes sense to send one in on the pickup along with my commercial stuff now and then. Granted my Silverado doesn't need 8 qts, but it gets a diet of synthetic also. But I get my synthetic from Schaeffer Oil for about $5.50 a quart, delivered free to the house.
I guess the major question would be for Toyota would be, what is the major issue with E85 that makes them feel the OCI needs to be substantially shorter. That is the first OEM I have heard of doing something like that on a flex fuel engine design. Oh well, one learns something every day. Probably not a good idea for you to use E85 then. I filled up today again with E85 at $2.64 a gallon. Only 3 mpg loss over using regular and regular is 3.45 right now near me. So a roughly 80 cent spread. Now, based on the 17 mpg average with regular my Silverado gets mostly running rural two lane and farm roads, that is a little over 20 cents a mile for regular. With getting around 14-15 mpg on E85, the cost is ballpark 18 cents a mile. almost a 2 cent a mile saving. Not much, but it makes it worthwhile to use E85 in my pickup. And even the OEM hp/torque charts on my engine show a 6 hp and 8 lb torque increase across the rpm range using E85 over regular. Sounds like a decided win-win.
I guess each persons has to weigh the issue for themselves and make their own conclusions. No wrong answer here either! I may use E85, but that frees up more gas for those that don't. We all win!
Oh, and the tax thing, the 52 cent tax at the pump is for every gallon of gas, E10, E15, E30 or E85. That is Federal and State fuel taxes on a gallon. Usually a few cents higher on diesel. It does reveal something that some don't realize. Some may blame the ethanol producers and corn growers for the mandates on ethanol, but in reality, it is because of the more fuel taxes generated by use of more fuel as a result of lower mpg that the politician have embraced the ethanol gig. Always follow the money trail. Sure, the ethanol folks are taking advantage of the mandates and such, but it is the hired help in D.C. and state capitols who need to have the bulk of the blame laid at their door step.