Timing chain requires you two take off the cylinder head and bottom 2 oil pans. I had the same chatter. Replaced chain tensioner first which did not fix it. Removed head. Chain was stretched. Timing chain guides were worn. Just about done putting it back together today. Did all the "while you are in there PM". Headgasket, valve seals, gaskets, o rings, injectors, hoses, phh, power steering, vacuum hoses, etc. I think it is worth doing this if you are doing timing chain. I did all work myself. Not a mechanic by trade . Shade tree. Took me total of 60 hours. I was anal about doing it right. Get a FSM. It will definitely take more than one day. Need an extra vehicle. Beno was awesome with parts he will hook you up. Get the complete engine gasket kit. Great thread s out there. Let me know if you need advise.