Is there really a big difference if you use regular, mid-grade or premium in gas mileage? I heard that it doesnt matter if you computer isnt programmed for it.
It doesn't effect fuel mileage unless you're running high compression or other mods. I've noticed a change in mpg when going to Level 2 or 3 with my edge and running 89 or 91 octance.
Iv never noticed a difference between them, and I ran all of them from time to time in my old ranger...after trying them all I just run 87 in my truck because its cheaper
i agree with old skl....only costs a buck or so more per so many gallons plus if i run 87 i get this odd noise from my cats....almost like a chinging sound, if i run 89 never hear it...
Run strictly 87, with a 93 tank run through it every 4 or 5 months. I have heard running the wrong octane rating can cause ping/pre detonation or carbon buildupo though.
I run 87 unless i am going to be making a trip then i run a tank of premium just to help burn any thing off the inside, then back to the 87 the rest of the time.
