Pennzoil Platinum 0w20 SP noisier than SN?

For example, the Afton HiTEC® 11410 passenger-car engine-oil additive package reduced-SAPS top-tier additive technology, ACEA 2016 C2/C3/C5 & API SP is 177 cSt:


Incidentally, seeing how these cheap generic add packs are ACEA & API dual-certified, we know how the European oils are overrated over API oils.

The best information about how the viscosity depends on the base oil, DDI pack, and VII with tons of systematic data can be found in the Hugh Spikes paper. It is open-access:


OK, so are you just fudging it based on a rough guestimate? As I said, I came up with 48cSt for that particular oil, but clearly it is going to vary. If I can make a suggestion, how about a column that just has BO KV100 (no DI package) and then one with the combined like you are doing presently?
 
OK, so are you just fudging it based on a rough guestimate? As I said, I came up with 48cSt for that particular oil, but clearly it is going to vary. If I can make a suggestion, how about a column that just has BO KV100 (no DI package) and then one with the combined like you are doing presently?
No, I can't estimate the viscosity of the unblended base oil without the DDI pack merely from the data for the finished oil. I can only estimate the viscosity of the blended base oil & DDI pack, along with the VII content.
 
No, I can't estimate the viscosity of the unblended base oil without the DDI pack merely from the data for the finished oil. I can only estimate the viscosity of the blended base oil & DDI pack, along with the VII content.
I understand that's the case at the moment, but you do have several blending guide examples where that could be added, where that information is indeed available (or able to be calculated, because the bases are called out, along with their percentages). Might be a fun project, lol.
 
Working that backwards, you've got the DI package with a 100C visc of 48cSt, which, if accurate, yeah, would definitely have a pretty big impact on the viscosity of the base oils it is being mixed into.
Also note that the simple viscosity-mixing calculators based on the Arrhenius equation don't work for dissimilar fluids. In this case, PAO and detergent are very dissimilar. See my thread on the Lederer–Roegiers equation, but it requires empirical input to work.

 
Also note that the simple viscosity-mixing calculators based on the Arrhenius equation don't work for dissimilar fluids. In this case, PAO and detergent are very dissimilar. See my thread on the Lederer–Roegiers equation, but it requires empirical input to work.

Yes, I remember that thread, but of course we have absolutely no idea of what alpha would be for the DI package.

Farting around with alpha, if I use .5, we get pretty close to the 177 figure (172) but of course we are just guessing 🤷‍♂️ Alpha = 1 yields 34cSt. So there's a rather broad spectrum there.

Still hoping HPL can provide us with some actual KV data.
 
Still hoping HPL can provide us with some actual KV data.
As I said, there is a multitude of data in the Hugh Spikes paper. An 11.9% DDI pack is increasing KV100 by about 1/3 (33%):


I also noticed that the DDI pack shears quite a bit at very high shear rates (full shear), above 10⁶ s⁻¹. At full shear, the DDI pack seems to lose about half of its viscosity contribution, so, down to about 1/6 from 1/3.


I am listing the base-oil viscosities at full shear (very high shear rate). Therefore, if my base-oil KV100 is listed as ~ 5.9 cSt, the base-oil KV100 without the DDI-pack contribution should be around ~ 5.0–5.4 cSt (reduced by ~ 8–14%), depending on how much DDI was used, which is probably not a lot in the case of M1 EP 0W-20. I know Mobil 1 likes to keep their base oil somewhat on the thin side and use a good amount of VII so that they could boost the fuel economy. If they are using about ~ 12% DDI pack, perhaps their base oil is about 5 cSt, roughly half and half SpectraSyn 4.1 cSt & SpectraSyn 5.8 cSt, and they are adding about ~ 4.5% OCP VII as I estimated in my base-oil viscosity & VII calculator sheet.
 
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As a more accurate number, a 40/60 SpectraSyn 4.1 cSt & SpectraSyn 5.8 cSt, respectively, mixture would correspond to a KV100 of ~ 5.0 cSt. There is also some AN in the mix. There is probably some Group III as well. This could be closer to the M1 EP 0W-20 base oil.
 
That sounds correct. API SP versions are a lot thinner than SN versions because SP emphasizes fuel economy over engine wear. By thinner, I mean they use a thinner base oil and more VII. Base-oil viscosity (HTFS) is what matters in the valvetrain and timing chain, not the kinematic viscosity (KV) or HTHS.

These are the base-oil viscosities (HTFS):

PP 0W-20 SN: 2.2 cP
PP 0W-20 SP: 2.0 cP

PP 5W-30 SN: 2.5 cP
PP 5W-30 SP: 2.2 cP

So, the new PP 5W-30 is as thin as the old PP 0W-20.

Estimated base-oil viscosity (HTFS) and VII content of selected oils
It's interesting that "API SP versions are a lot thinner than SN versions because SP emphasizes fuel economy over engine wear" and yet SP versions are claimed to reduce timing chain wear. I assume the reason is what you mentioned about the DDI package being more viscous in SP oils?
 
It's interesting that "API SP versions are a lot thinner than SN versions because SP emphasizes fuel economy over engine wear" and yet SP versions are claimed to reduce timing chain wear. I assume the reason is what you mentioned about the DDI package being more viscous in SP oils?
Timing-chain wear depends on the additive package as well as the base-oil viscosity. No, the DDI pack isn't more viscous for SP, besides my viscosity numbers include the effect of the DDI pack.
 
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I think anyone who claims they can detect a meaningful difference in engine noise levels within the same grade is out of their mind and they suffer from BITOG psychosis.
 
The latest VOA indicated that the Moly is at bare minimum and zero Boron. This might contribute to the louder noise.
 
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