I'm on my 5th OC of PUP with my 2016 CRV with the K24W gasoline 4 banger. I am temped to run 4 OC of VRP but that engine idles like a fine swish watch, and screams like an abused ape when I asked it to in Sport mode climbing up winding steep hills passing slow drivers like they were driving something running on a few missing cylinders.
I recently saw a YT video where someone showed testing an engine for blow-by by setting the unscrewed oil fill cap on the fill hole while the engine idled to compare an engine that used VRP to an engine that used PUP, so I did that and it did not raise up. Vibrated a bit, but no raising up. And looking down in the fill hole past the fill screen, with a bright light, I see Uber clean valve adjustment and surround area.
I put the maintance dose of 4.45 mL of Red-Line SI-1 per gallon in the fuel tank before each fill up, and also have ran a few tanks of high dose ( 3/4 bottle to 15 gallon tank ) of SI-1 over the years. So that engine probably has very clean injectors, and SI-1 in fuel + PUP in the sump, probably means very clean piston rings. I think I'm staying with PUP.
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BTW, one reason PUP got bashed is because the VOA now shows lower TBN. But with its great base stock, wise blending of additives, and today's low suffer gasoline, the UOA's have ALWAYS still shown acceptable TBN. So if it ain't broke don't fix it Tony. It's lower TBN is totally adequate, and probably allows the formulators to put in more good stuff of other additives to do other things well.
Bottom line, PUP is still a FANTASTIC oil. Probably even improved now with reduced TBN allowing better other additives acording to Lake Speed Jr..
Pennzoil does need to do better advertising of showing more engine teardowns of engines that used PUP for many miles, and also highlight how clean the piston rings are.
