Originally Posted by Fully_Bolted
I think you are chasing unicorns here. No one is going to make a blanket statement, such as AAA, giving an "All Clear" to use E85 across all makes and models. Is Ethanol safe for all makes and models? Hell no. Is it safe to use in >2007 BMW 335i? I would say Yes.
To have a definitive answer, someone would have to study our engine and fuel system components during E85 use and over a long period of time.
I did post something longer here, but, I realized that I am definitely not chasing unicorns. Ethanol usage in fuel is such a large topic that there would surely be more analysis done on corrosive properties on a component-by-component basis, and an analysis done on the degradation in performance of certain engine components. There is a whole market of Flex Fuel vehicles that have been subjected to regular ethanol usage, with mechanics around the country seeing the effects on engines that have seen more ethanol, vs. less ethanol. There is a lot of data out there, but there does not seem to be much in terms of compiled studies. You don't necessarily need to put a whole car together and test the effects holistically. Car companies are able to issue warranties for cars with engines that have never seen a long term test (much like our own cars when the N54 engine first came out), so, it seems that one could establish enough confidence about long term ethanol usage.