Originally Posted by Gokhan
Now, surprisingly, Pennzoil Gold 0W-20 virtually ties with M1 EP 0W-20 in (lack of) VII. In fact, I assumed HTHSV = 2.6 cP for it and if HTHSV is higher, it would readily beat M1 EP 0W-20. M1 EP 0W-20 is only second to M1 ESP x2 0w-20 (an MB 229.71/ACEA C5 oil), which, along with M1 AP 5W-20, has less VII than any oil listed here except for the monograde Amsoil 30 (also qualifies as a 10W-30), VAS 5W-20, and Delvac Super 1300 15W-40.
So, it's hard to believe that Pennzoil Gold 0W-20 is a synthetic blend. It's possibly a full synthetic. It readily beats PPPP 0W-20 and PUPPP 0W-20 in VII content.
Regarding how the engine sounds, well... I really like how M1 EP 0W-20 SN PLUS sounds in my engine. Who knows, perhaps I'm hearing the metal grinding away, but I like the sound.
It sounds like the engine has lower friction with it in my perception but if some interpret it as the engine being louder, which I didn't notice, it could be more of a perception issue than a scientific observation, until people grab sound-level meters and start scientific observations.
I think we need to hit pause here for a second. Does it not strike you as odd that M1 EP 0w-20 would have a 5.5% VII treat rate and its sibling, AP 0w-20, which has the same amount of PAO, is 10%? Both have almost identical VI's too. Doesn't smell right to me
Also, AP Flash point: 242C, EP? 235C. I'm guessing the HTHS for both of these lubes is rounded. AP could be 2.64 and EP could be 2.65 for example, and that's skewing the calculations.
Playing around with the calculator using the above theory:
EP:
A_Harman Index: 0.926
AP:
A_Harman Index: 0.913
BTW, I noticed you used the KV40 for AP 0w-20 from the MSDS. I'd be hesitant to do that and here's why:
The MSDS for EP 0w-20 lists:
KV100: 8.4cSt
KV40: N/A
Flash: 235C
Pour: -45C
The MSDS for AP 0w-20 lists:
KV100: 8.7cSt
KV40: 45.7cSt
Flash: >200C
Pour: -45C
We know that the Pour Point is wrong for both of them. KV100 is wrong for EP and KV40 isn't even listed. So I'd be skeptical of that number IMHO. I'd wager both have basically the same VII content and the deviation we are seeing here is the result of rounding.
For Pennzoil Gold "blend" 0w-20 BTW, I think your sniffer is working properly. The MSDS shows 70-90% GTL
I'm going to say that the lack of digits after the decimal for the KV values is, at the resolution we are trying to achieve here, screwing us, for example, using the Gold w/HTHS 2.6:
KV100 8.44, Index becomes 0.937.
If rounding is allowed in HTHS, IE 2.58 can be rounded to 2.6 then that adds another layer of fudge factor here