This is my first time asking this here. Just figured I might get new opinions. So it starts between 50-55. maybe before but i cant feel it. And all the way up until around 70mph then its gone. I have no idea what this is. If i take it out of OD into 3rd it will start jerking like crazy. Tranny fluid and filter just replaced, new TPS, new intake gaskets, new plugs, wires, cap, rotor, dizzy inspected and tested. When doing tranny fluid change the pan showed nothing out of the ordinary. I also get a random misfire occasionally under heavy to wide open throttle. Havent had that lately but the truck is still doing this. It especially does it using cruise control. Any ideas? Im thinking maybe ignition coil, EGR valve, or my screaming fuel pump. I have a very low idle on startup and then it idles up after a few seconds if that could be related to my issue.