hello hope someone here has possibly had this same issue my truck is a 04 4.6 f150 had a knock last year which was a bad plug,#2 but recently seemed to have a knock again under load never showed itself alot then towing a trailer on the interstate last week had a whining and then a loud persistent knock on the passenger side was able to dive it home another 15 miles but can not seem to locate this problem have taken the valve cover off and chain is tight also removed 4 lash adjusters and have not found anything obvious dont know if i am going in the right direction the motor has 82000 on it oil was always changed with motorcraft and filter also ,tried some tranny oil in the crankcase first and lucas also ...any ideas would be helpful or mabye just a new engine seems odd though truck has been taken care of ..thanks ...dave