I try to use Chevron 89 as much as possible. No one has brought up stations that broker for fuel and are usually cheaper. These guys get whatever is overstocked at the refinery for way cheaper than the franchise station, so that cheap station may have Chevron or Shell and selling it for 10-15cents cheaper. I avoid Arco gas too much water, and Ethanol fuels. Ethanol has a slower burn rate like high octane fuels, and in a low compression engine is a waste unless you have 9.8 or higher compression (though my Cherokee does like 91 sometimes). Also from having run A 10% ethanol fuel in my 4.0 for a few months that stuff kills Exhaust valves.

 

Always try to get Shell gas. 87 octane for daily driving, 89 if I have to do long highway trip.

Throw in some seafoam once a month and it's good to go. Anything higher and my engine doesn't like it. Hell my buddy got worse mpg using the higher octane. I guess each XJ has it's own taste! I get the WORST mpg from Sunoco...don't know why

But don't go putting the funky no name gas in your tank. Try to stick to the Shell, Exxon type

 

I generally run 85. I just put in a can of bg44k with 91 and my motor is loving it!!!

 

And they use diesel tractors to grow the corn, fertilized with more petroleum/NG products, then transported by diesel trucks to the ethanol plant, with the end product trucked again by diesel or diesel-electric locomotives..
It's really a net loss as far as oil use is concerned. It takes more oil to produce ethanol than it replaces.
It's production also creates more greenhouse gas than is saved by any E-blend. It is an entirely a giveaway to the corn industry and not an inexpensive one.
My idea of energy independence isn't a fuel that uses more oil to produce than it saves.

 

I use 87 which is the lowest in my area, and my favorite station is 76. If not available, I will go to Chevron or Shell. I refuse to go to ARCO, Sams Club,Costco, Grocery Store, and other discount stations.