Some days when I start my truck it has a bad shake to it. After it warms up, however, it starts running fine. Well, better than it did when it was cold. Then, somedays it runs fine until I travel a distance then i can notice a loss of power. And yet on other days, there seems to be no problem at all. Most of the time I drive my truck to and from work which is less than 10 miles away. For the most part it drives like there is a loss of power and I can't figure out what it is. There is no check engine light coming on so I can not pull any code. I drive a F150 4.6 4x4. any help would be much appreciated. if you need more info just ask and I will give you all I can. I am thinking about taking to the dealership to see if they can diagnose but I don't know if it will be one of the days when nothing seems wrong and it costs me an arm and a leg to have them say there is nothing wrong with it.

Thanks
Jeremy