I have been on the fence regarding 0W-20 versus a thicker oil in this engine. I have a friend down the street who runs 0W-40 in his 3.6L and he has not reported any issues by doing so. Curiously enough, his oil pressure is the same as mine and with no BPV in the oil filter (it is a cartridge), I wonder what the internal bypass pressure is as I would have assumed he would see a marked pressure difference (at least when the engine is cold).
I added a catch can to mine (UPR) and initially (after about 200 miles) it had only trapped about 1/2 teaspoon), however, it now (after 600-700 miles) has trapped a few ounces of oil. I attribute the initial low amount to the hoses and filter media being dry because they were new. This is oil that would have been introduced into the intake system and subsequently burned in the combustion chamber. I added this text because it is strange the 3.6L has that much oil vapor in the system, yet has tight valve seals--to wit what is causing the vapor? The oil type does not seem to matter either based upon what I see posted in a couple of the Jeep forums, even oil with good NOACK ratings produces oil that is trapped in the catch can.
At any rate, really nice to see a Pentastar (especially a Gen 1 that had head issues early on) with that many miles on it. The 4 bolt mains and the size of the main and rod journals likely contribute to their durability and I assume those carried over with the Gen 2 engine (which is what the Jeep JL Wranglers have). FCA re-designed the heads and valvetrain, though I do not recall reading anything about the timing chains or improvements on the timing system on Gen 2 engines.
After seeing the video--what are your thoughts? 625K is a great run and 0W-20 (what is specified for the Gen 2 series, though the Gen 1 had 5W-30 specified in different parts of the world) is just fine or would you up the viscosity to an xW-30?