I haven't had the time to look over all of the truck but I noticed this morning that when I shut the truck off it acts like everything stops faster and there is a loud rattle that sounds like one of my loose tool boxes but its coming from the front half of the truck.
I could be wrong about the truck shutting off faster but the rattle is not in my head .
I have also noticed, but I am not sure if it is a loose wire, my rail pressure will idle about half of normal at some points (sometimes all the way down to triple digit numbers) , but then pick back up to normal and I can't hear the change.
I don't notice any abnormal smoke or idle, but since it started having a weird shut off it also sounds like its being restricted on start up.
Could this be a fan clutch symptom?
Could this be a CP3 or injector problem?

 

No takers?