Well it sounds a lot like lifters.  Geez, that engine is dirty inside.. 

Here's the old fashioned repair, and this worked for me on mine when it started making that noise at 180K..  change the oil, and substitute one of the quarts of oil with Dexron ATF.  Drive it around for a couple hundred miles, then pour in a can of Seafoam.  Yes, pour it right into the crankcase.  Drive it around for a couple hundred more miles, then again change the oil.  It should stop making the noise at some point during this procedure-mine did.  This is the old fashioned way to free up a sticking lifter, which you hope is the source of that noise :-)

Be sure you are using Mobil-1 synthetic 5w30 oil.  And if this fixes the problem, again pour in a can of Seafoam just a few hundred miles before the 3000 mile engine oil change.  Which you should do if you want another 100K out of that engine.