Hello everyone, this is my first time with a question, so please bear with me if I don't do it right. I have an 08 f350 super duty 5.4l 3v. I have had a timing chain rattle on cold starts for about a year or so. Both vct solenoids were changed last year, and last week I decided to pull the timing cover to see where the rattle was. The right side chain had slack, while the left side was tight. I bought a new tensioner and the rattle went away for about 1 day, then it returned again(only a slight rattle now). There are no other issues with the engine, it runs like a champ. Any ideas as to why it still rattles on start ups would be grately appreciated. I just recently changed from fram oil filters to motorcraft. My boss also likes to add lucas oil treatment to everything, despite my pleas to adhere to Ford's recommended 5w20 instructions. Thank You in advance for any help. Steve