[Ymryl]

The computer in your Armada (or any other recent year model vehicle) automatically adjusts over time to run optimally on whatever grade of gasoline that you put in. If you are running 87 octane (as I am), don't expect to dump in a tankful of 93 octane and see a huge difference in performance because you wont. If you run several tanks of 93 you may see a bit better gas mileage but with todays gasoline prices, the benefit hardly outweighs the price at the pump.