Update I went on an unexpected 320 mile road trip yesterday and I could see a difference in the way the truck drove with the programmer installed and best of all my gas mileage went up very nicely exactly how much I don't know yet but I can really see. Before it would take almost 3/4 of a tank for the 1st leg of my trip this time it was only about a half tank and that was with the a/c on and doing 80 mph the whole way there and back. So needless to say I am impressed.

 

Another update on mine,
I decided to stick it over to the premium setting, nospark knock.
Wesco around here sells midgrade for the same price as regular, so im just useing that and it seems to be fine.

Power really woke up too, I like it!

 

I tried mine on the premium setting this aftrenoon and I could tell there was a difference in the power but I did get a little spark knock at full throttle it even threw a code... misfireon thenumber one cylinder. So I set it back to the 87 octane and everything wass fine again.

 

I think I can get away with it because of the 89 octane gas, and the fact that our altitude is practically sealevel.

 

Do they sell 93 octane where you guys live??I only see 91 octane at the pump not 93 what the programmer requires.Also do you think that it makes a difference whereyou are buying gas as in Chevron, Shell or lets say Walmart gas??