04 lly, 7000mi, 100% stock, empty truck, never pulled anything, don't think it would any way, fuel up at truck stops only, to the dealer twice, last time with reflash. Idle surges when stopped. Terreble fuel knock when under any type of load (giong up a slight hill). I can push the peddal to the floor in any gear and it totally falls on it's face. After a 2 or 3 sec stumble it will finally start to wind up and go. It's like having a rubberband foot feed, if I stretch it far enough it will respond. Back to the dealer mon. I have driven 2 other lly's, wow , night and day difference, no knock and lots of power. :mad:

something is definitely wrong if thats whats happening with your truck ! stock i can tow my toy hauler up and down hills, granted i need more power so i can hammer past the slow polks when towing but thats when the TTS Tow tune comes in handy. Back to your truck though, theres gotta be something wrong if it feels that bad - i would go to your dealer and demand they figure it out, drive it with them, let them drive it, then jump in another one on the lot and make them see the difference if they cant figure it out

Good luck! Been there done that. Thanx Geo.