None of your diagnostic techniques will pinpoint a rod or main bearing failure. Head to NAPA, buy a pack of plastigauge. It is a squashable thread that is placed between the bearing and the rod/main bearing journal. The cap is then installed and torqued to spec. When removed, the squashed plastigauge width is compared to the clearance patches on the package. If a bearing is bad, the plastigauge will never be squashed, or it will be squashed way too little indicating the bearing clearance is outside specification. What was the oil pressure at idle, 2000 and 4000 rpm? There are two other explanations for this noise but neither of them appear from the video to be applicable but I will mention them anyway. 1) The 3.0 uses timing gears rather than a timing chain. If the noise goes away or at least diminishes as you rev the engine, it is possible the cam gear is bad and has become sloppy. That noise is more at the front of the engine. 2) Mechanical FUEL pumps have a push rod actuated lever. I've seen the return spring fail on the pump and believe me, more than one engine has been torn down and inspected only to find nothing wrong. That bad spring can make the pump sound like a rod bearing failure. You already know this, but you pulled that engine way too quickly and did not follow much of the advice previously given. The engine idles too smoothly to have a stuck valve. You should have followed your mechanic friends advice. It is a very simple task to pull the rocker cover.. As for the oil pump causing the failure that is highly unlikely. Oil pumps are almost never the cause of bearing failure and replacing the pump is never a fix for low oil pressure. However, oil pumps should be replaced as part of a rebuild since you are in there anyway.
