Thanks guys! I'll check the harmonic balancer first. Not sure if I can drop the pan in the truck. I've never tried that. I did toss the filter already. It is no longer available. It went out with the recyclables this morning.
Hopefully, it is just the harmonic balancer, but I kind of doubt it. My first thought was a stuck or collapsed lifter, so I put an oil treatment in for that. Knock got worse. I dumped that oil and filter and put in all fresh and it went back to what it was. Makes me think it is bearing related, but I can hope for a simple fix.
