[WySilverado]

I also did the HC mod but didn't reset the Computer.I'm at 13,000 miles with a K&N drop in since 1000 miles.377.3 miles on 22 gal is 17.5 mpg.Thats from Powell WY (4500ft) to the top of the Big Horn Mtns(close to 9000ft) and back(100 miles round trip).The other 270 miles was to work and back which I usually get 14mpg.I guessed with the 100 mile road trip I'd average out at 16mpg or so.17.5 is insain,only got better than that on two tanks on a Vegas road trip.I just fueled tonight,the next week and a half of normal driving will tell,no road trips,no ecm reset,just the HC mod.My normal tanks of regular driving (around town)are worst of 13 in the winter and best of 14.7 just 2 tanks ago.Best ever was 18.6 hwy.