One morning I started my truck. It had a loud rattle so I shut it off and checked everything out then restarted. No noise so I went on. When I got to where I was going I smelled burning oil. After limping it home I found the right valve cover was busted. After getting it off I found the timing chain cassette had broken and flew up into the valve cover and busted it. I started tear down June 28th. Just one month after having back surgery. Lol... Once the engine was out and on a stand I could sit and do most of the work. I was able to do the chain replacement without removing the heads which was nice. I replaced timing chains, cassettes, and both valve covers.I have to give a big thanks to this site and explorer forum for instructions on doing this job. I am a mechanic but ive never done a timing chain on a 4.0L SOHC. Anyway I just wanted to thank this site for the help and if anybody is doing this or needs some answers I can help out.

 

Glad you got it figured out :)