[Xtremjeepn]

Why 89 octane???? 87 is all that is required. Pouring money down the drain.

Technically that depends on your elevation.

 

[Xtremjeepn]

High altitude uses 85 octane. 89 isn't necessary anywhere.

Our mid grade at 5,000 is 87. 91 is Premium. (no 89 here)

Keep in mind that the pumps already adjust for altitude, if you also adjust to a lower octane then you are too low.