I have a 2004 6.0 powerstroke. F-250. I've had problems with it stalling surging, missing. So I've cleaned the EGR, IPR, and the ICP. It runs a little better now but still skips, shakes, and doesn't want to shift properly. Doesn't a little better when warm. What do I look for next. The oil has been changed and treated. And also have dropped the tank and cleaned with new filter installed and fuel treated. I used revx treatment. Any help appreciated.