Re: For 5.7L HEMI: what octane rating of gas do you use?
The only time I ever put 87 octane in is if it has no ethanol. If 10% ethanol is involved, it is always 91. I know 91 has no benefits over 89 octane normally (unless your engine is tuned for it with a programmer, of course), but when you throw 10% garbage in, it seems to like the higher octanes a little better.
2014 Jeep Grand Cherokee Limited 4x4
5.7L Hemi V8, Luxury II Package, Navigation
Hemifever Tuned, Billet Catch Can, 265/60R18 Hankook Dynapro ATMs