Sign Up! To view all forums and unlock additional cool features
Welcome to the #1 Explorer ST Forum and Explorer ST community dedicated to Explorer ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Explorer ST Forum today!
My manual states that 87 is the minimum. Then 2 paragraphs later it says. "For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended..."
I fed mine 93 during a 2,600 mile road trip last summer. Avg 24.2, best 26.4. SInce we got back, I switched to 87. My fuel cost per mile is lower, but that's mostly because the 93 averaged about $5.20/gallon Since I putter back and forth to work and run errands, the extra ponies don't seem to be needed. I'm pretty sure 93 would give me cost-per-mile that's comparable.
Ran 87 since day one, switched to 91 when I had to do a little towing. Never noticed much if any performance difference. I’m sure a dyno would disagree, but by seat of the pants, nothing noticeable.
based on how much I drive the general 50-70 cents increase for 93 octane, it costs me a few extra hundred dollars a year. Definitely worth it especially tuned.