I'm going on a trip at the end of July and would like to get a little better than 13 mpg out of my suburban. I have EFI Live and have tuned my LB7 Duramax(500+ hp and still getting 20+mpg), but gassers are a bit harder for me, especially with no A/F meter or a dyno. Would anyone be willing to post up their tunes for a 5.3 or give me some tips to help improve mileage, like what tables to adjust and how far to adjust them? I would prefer something that I can just look at and adjust a few things like rear end ratio and tire size and load into my truck as I don't have very much time to mess around with tuning, but any help would be greatly appreciated.