I am not sure if this is top end or a rod knocking, but I am pretty sure it is internal engine noise.

 

Just got the Jeep back from Warranty Extended Service...

Lifters, Heads (They said valve seats were dropping) and Rod Bearings ...

 

Wow thanks for the update!! 2 months they had it .. eyikes. Makes sense Rod bearings = low oil pressure = lifter tap. Dropped valve seats ... Usually they drop from heat cracks in the cylinder head from lean conditions. The way the 3.8 02 sensors read I doubt it was a lean heat but rather lazy exhaust valve opening that held heat ... kind of heat. So it all makes sense. .... all but Rod bearings @ 48,000 miles