[Weekend Pundit]

Originally Posted by John Mercier

https://www.mnbiofuels.org/rfa-revie...for-flex-fuels

So which vehicles are currently under warranty that manufacturers are warning about?

The linked article addresses the warranties on 2020 vehicles. Then there's this from that same article::

"Automakers did not start including E15 as an approved fuel in owner’s manuals and warranty statements until 2012, the year E15 was first sold commercially." Not all vehicles were approved for E15 then. That's when the automakers started approving it, and it wasn't an across the board approval.

My 2014 RAM 1500 isn't approved for E15. It is still under warranty. My 2004 F150 isn't approved for E15. (It is no longer under warranty, obviously.)