@Burla, there is more to motor oil than Moly. Both Valvoline and Royal Purple (Calumet) tried to save a quarter. They wound up losing millions in profits because other than a small loyal following (weird), no one is buying them, especially Royal Purple. The formula is not standardized. It's Lubrizol that is selling Valvoline, a finished additive package, pure and simple. They put Moly in oil to pass the timing chain wear test, which is a cheat, by the way. But I don't want to go down that rabbit hole now. The point is that motor oils made with poor quality base stocks that don't have friction modifiers to compensate for what the base oil can't do will lead to additional wear, pure and simple. Was Castrol EDGE 0W-40 on that list? I doubt it.
@Hemi395 The link between PYB and quiet HEMI is the density of the oil. It's a group II oil that is much denser than synthetic, but it's not consistent in its density, so it's not good for long OCIs. Red Line is much denser than any oil on the market and uses quality VII, so of course, it quiets down a motor with loose tolerances in some parts. And it has POE that is basically a solvent, so it cleans really well. Moly is not the only thing in Red Line that makes it work, not by a long shot. Actually, RL has been cutting down on Moly lately. It's not that PP, PUP, Mobil 1, or other oils are bad, but rather that they're made for modern engines that are manufactured better. The HEMI has Q&A issues, so you're better served by a thicker oil. Pure and simple. And it has to be a quality oil as well.
And finally, I don't get people that use HD Diesel oils in their gasoline vehicles. The Subaru crowd loves Rotella T6, which is insane. That oil doesn't take into account timing chains, soot from gasoline, and many other things. Why do you guys think that Chrysler has a different standard for the EcoDiesel? They recommended Rotella T6 for that thing when engines running Pennzoil Euro L 5W-30 started showing up with spun bearings. The Rotella T6 was a stop-gap until Shell finally made a 5W-40 compatible with the EcoDiesel, MS-12991. That's because the EcoDiesel has a timing chain and because it was developed as a passenger car diesel for Europe, and an ACEA C3 oil like EURO L 5W-30 would have been perfectly fine for it. But when you put a diesel with tiny bearings in a truck and run PCMO oil in it, things tend to go south really fast. Of course, I couldn't convince many of these people that they're wrong unless I showed them the inside of a truck engine. It has timing gears, ceramic rollers, and a single forged cam. They're all similarly built, except when they try to save money, they cheapen some of them. That's why these truck engines go for so long, whether idiots run Lucas in them or go 60,000 miles on AMSOIL because their AMSOIL dealer said they should. It's not the oil so much as it's how they're built. So HD Diesel oil is not nearly as good or as "stout" as people think. And it doesn't have "a dose of moly" or a "shot of boron" usually. It's just oil and relies mostly on the base stock to do its job. Oh, and most HD 15W-40 Diesel oils don't really have friction modifiers because they don't need them in a truck engine.
If Moly was the end-all-be-all, then we would all be running TGMO 0W-20 in our HEMIs (700+ ppm) or Mobil 1 0W-30 Racing Oil (1600 ppm).
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One more thing that grinds my gears: how many of those Las Vegas taxi cabs used to qualify motor oils for MS-6395 (0/5W-20/30) and MS-12663 (0W-40) are actually running HEMIs under the hood? Yeah, it's amazing when one applies logic to nonsense, lol.
