I have been reading this board for a few weeks now and enjoy the informative dialogue. I recently purchased a 1999 F150 4x4 with the 5.4. It had 40,000 miles on it when I bought it and noticed the burning oil smell that unfortunately was the head gasket issue. Fortunately for me though, the dealer I bought if from replaced the engine with a brand new crate motor at no charge to me. I'm very happy with the truck except for one thing. At idle, I notice a very slight bump that feels like a very small miss. I have read the multiple threads on this board dealing with the rough idle and just wanted to know if this is what everyone else is experiencing when you refer to a "rough idle?" My tach never moves when this happens and it runs fine otherwise. Should I even worry about this? I have put approximately 1000 miles on the new motor and this problem has not gotten any worse or better.