Aaah, now I understand what you want to say with "average"
But, be sure - in the manual will never ever be "87 Octane is acceptable" if it would harm the motor only a tiny bit.
For (my and the most others) daily ride with an empty truck to work and back, without hauling, without higher speed (the stock ram is limited and don't run faster than only 170km/h - 105mph, that's very slow and not what I call high speed) the 87 octane is good enough. For my daily ride in the city I save my 10 Can$ per filling. Maybe I loose couple % in power but the Hemi have still way enough power. When I want a sooo much a faster truck, I can maybe loose 20lbs at my belly, that helps too
I tried the 89 octane gas for some fillings and I don't note that I need more or less gas than with the 87 octane. All was the same, but not for my wallet.
But how I said - if I would haul, maybe heavier stuff, maybe hill up and down and at the Highway, than I would use 89 octane Gas.
More octane than 89 octane is wasted and burned money. Better sent the money to me - I will say some magic spells for your motor, that works as well
