Update, today I filled up with 89 octane and my truck is runnign just as well! :D

I am no engineer or a chemist, the info I give is what I have heard and read from engineers and chemists.

For instance Amoco had to stop it's ad campaign about its high octane gas because it was causing problems in lower octane engines.

To re-word what jstang says, higher octane burns slower than lower octane and if your computer is not set up for the difference you will get build up. And if you keep using it yeah you won't get knock/detonation as long as you keep using the higher octane.

I can't stress this enough, these are modern engines! They are designed to use a specified octane. What worked in the past doesn't work now. If this old fashioned "I've always done it" theory was correct it would be fine to put a LOWER octane in a higher octane specified engine and it would be fine.

If your engine pings/detonates THERE IS SOMETHING WRONG! get it fixed don't just put a higher octane band-aid on it.

This is just my .02 as always you do what you want and what you think works for you!

Have fun and enjoy your trucks!

Peace

I agree.... I used 89 octane gas for the last two years to cover up a pinging issue I had during the colder temperatures in the winter. While useing 89 octane gas completely took care of the problem a couple years back when I started useing the higher octane gas, over time it has helped less and less. Last winter I began getting minor pinging again with the 89 octane gas. I just recently went back to the 87 octane because my issue with the pinging is non existant from about April on after the temperatures warm up. If anything I've noticed my truck runs better here in the last few weeks with the 87 octane gas.