What Rob posted earlier in this thread is what the manual says.I know this is 4th gen, but my 2015 manual says “Regular unleaded gasoline with a pump (R+M)/2 octane rating of 87 is recommended.” That same paragraph ends with “Premium fuel will provide improved performance and is recommended for severe duty usage such as trailer tow.” Pg. 186
Does the 18+ EB state 87 is the minimum recommended?
Let me sum it up in one statement, "87 required, 91+ recommended."