So is there a recommended starting point? I will do very little towing and prefer to use 87 octane but if the other tunes will result in better mileage and life of the truck then I will start where you recommend. It's a 5.3 flex fuel but will never see corn (minimal anyway) in my truck.

I have an 08 Avalanche an I am considering a custom tune. I run 91 no ethanol from time to time. Do I need to be consistant with the type of fuel I use with or without the custom tune?

I would,like to,try to turn this of. Do I need a custom tune or .....?

I would,like to,try to turn this of. Do I need a custom tune or .....?

Got it all straighten out user error, cable is the right one. Tune installed 87 mpg boost, could be
not exactly the right name for tune. So I tried a couple of 87 octane tanks. I accelerated onto the highway today with some engine knock. Should i expect this? The wind has been so high that I ...

Thanks he also sold me the cable but I dont believe my computer has the serial fitting

I believe the revision is 9To9H but I did not see that on the download page.

I have a 2008 Avalanche and bought a used predator that was used on an 09. I can not use it because the message is tune is not supported. Is there something I need to do to make it functional?