valve cover

Driving my 2006 4.0L Inline 6 Yesterday, I started hearing a knock while accelerating, know I hear it while idling. About 160k miles on it and a brand new timing chain and assorted parts that come with it. I brought it to my mechanic and he said it was likely coming from the valves, but he would...

When you pull the valve cover and look at the underside of it (inside) the baffles up top - are they necessarily required? I hear a lot of people taking them out for clearance or otherwise... Thoughts?

Hey all, hope you are fairing well today. I’m running into an issue finding an inexpensive valve cover for my “06” 4.0L. Would I be ok to go with an “04” or earlier? I’m not sure if there is any difference.