2022 Mazda CX-9 - High Performance Lubricants PCMO 10W-20 - 4,897 Miles

So the HTHS is greater than 3.0?
Thats great, but I my thick skull is still having a hard time comprehending why that is better for a turbo engine that specs 30 grade.

Especially if they are buying hpl anyway, so why not buy the 10w30 or 5w30?

Looking at the specs, it is clearly less viscous than 5-30, 5-20 and 10-30 at 100c. With a VI of 128.

Per the KV100, yes. However, the bearings don't care about kinematic viscosity. They care about dynamic viscosity, particularly at high loads. This is where SAE J300 falls short.

Here's the HTFS for the 10W-20 compared to common 5W-30 and 10W-30 oils.

HPL PCMO 10W-20 = 2.72 cP
HPL PCMO 5W-30 = 2.59 cP
Castrol Edge 5W-30 = 2.26 cP
Mobil 1 ESP 5W-30 = 2.48 cP
Pennzoil Plat. 10W-30 = 2.65 cP
Quaker UD 10W-30 = 2.64 cP
Valvoline Adv. 5W-30 = 2.17 cP
Mobil 1 HM 10W-30 = 2.51 cP

That 10W-20 produces a thicker oil film than every one of those 30 grades. That's because it's using a straight 8 cSt base oil and not relying on VII to boost the KV100.

The main reason I recommended the 10W-20 to him is because of the high fuel dilution. VII polymers and fuel dilution don't get along due to the way VII works on viscosity. The viscosity loss from fuel dilution is more drastic when VII is present. In order to ensure good film thickness in the bearings in the face of that dilution, I wanted an oil with no VII. The 10W-20 fit that ticket with the HTHS knocking on 30 grade territory and the HTFS well into (and past) 30 grade territory.
 
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So from that spreadsheet, the HPL 10W30 PCMO has HTFS of 3.0 cP. Why not use that?

How accurate are the calculated values in that spreadsheet?
 
So from that spreadsheet, the HPL 10W30 PCMO has HTFS of 3.0 cP. Why not use that?

How accurate are the calculated values in that spreadsheet?

Because the 10W-30 contains VII. I didn't want an oil with VII due to the fuel dilution. It was in the winter when he put the oil in so we didn't want to use their SAE 30 due to possible pumping issues. Therefore, the 10W-20 was the way to go.

It performed well, still holding 8 cSt viscosity despite 3% fuel dilution. The wear numbers are low considering the engine is still breaking in.

The values of that spreadsheet are fairly accurate. The margin of error is provided on it as well.
 
Here's the HTFS for the 10W-20 compared to common 5W-30 and 10W-30 oils.
Did you calculate these values? That 10W-20 HTFS looks almost identical to Red Line 5W-30 if memory serves. The Red Line additive package is kind of antiquated ... If memory serves 😉
 
Did you calculate these values? That 10W-20 HTFS looks almost identical to Red Line 5W-30 if memory serves. The Red Line additive package is kind of antiquated ... If memory serves 😉

I did calculate it. It gave me the same result as the spreadsheet.

Redline HP 5W-30 = 2.84 cP

It's also worth noting that Redline HP 5W-20 is 2.65 cP. Some of the 5W-30 oils in the spreadsheet have an HTFS of
Here's the spreadsheet from Google Docs.

 
Per the KV100, yes. However, the bearings don't care about kinematic viscosity. They care about dynamic viscosity, particularly at high loads. This is where SAE J300 falls short.

Here's the HTFS for the 10W-20 compared to common 5W-30 and 10W-30 oils.

HPL PCMO 10W-20 = 2.72 cP
HPL PCMO 5W-30 = 2.59 cP
Castrol Edge 5W-30 = 2.26 cP
Mobil 1 ESP 5W-30 = 2.48 cP
Pennzoil Plat. 10W-30 = 2.65 cP
Quaker UD 10W-30 = 2.64 cP
Valvoline Adv. 5W-30 = 2.17 cP
Mobil 1 HM 10W-30 = 2.51 cP

That 10W-20 produces a thicker oil film than every one of those 30 grades. That's because it's using a straight 8 cSt base oil and not relying on VII to boost the KV100.

The main reason I recommended the 10W-20 to him is because of the high fuel dilution. VII polymers and fuel dilution don't get along due to the way VII works on viscosity. The viscosity loss from fuel dilution is more drastic when VII is present. In order to ensure good film thickness in the bearings in the face of that dilution, I wanted an oil with no VII. The 10W-20 fit that ticket with the HTHS knocking on 30 grade territory and the HTFS well into (and past) 30 grade territory.
I've always wondered about how VII and fuel don't seem to work well together. Gokhan talked about it in the past. I think that's one reason why Mobil 1 0w30 AFE loses substantial viscosity when there is fuel dilution. There was a recent UOA where it lost 36% of its viscosity in 3k miles.
 
The main reason I recommended the 10W-20 to him is because of the high fuel dilution. VII polymers and fuel dilution don't get along due to the way VII works on viscosity. The viscosity loss from fuel dilution is more drastic when VII is present. In order to ensure good film thickness in the bearings in the face of that dilution, I wanted an oil with no VII. The 10W-20 fit that ticket with the HTHS knocking on 30 grade territory and the HTFS well into (and past) 30 grade territory.
So, are you going to pay for a replacement motor if he has an engine failure, and Mazda denies his warranty because you used a non-approved oil weight in the motor?

If you were doing this to your own car, it's one thing, but in this case, you're risking someone else's vehicle.

BC.
 
So, are you going to pay for a replacement motor if he has an engine failure, and Mazda denies his warranty because you used a non-approved oil weight in the motor?

If you were doing this to your own car, it's one thing, but in this case, you're risking someone else's vehicle.

BC.

His engine isn't going to fail because of a 10W-20. Please read again the post that you quoted, then go look at the UOA.
 
His engine isn't going to fail because of a 10W-20. Please read again the post that you quoted, then go look at the UOA.
Is it going to fail? No.

But recommending non-approved grades and products to a vehicle under warranty carries some liability on your part.
 
Is it going to fail? No.

But recommending non-approved grades and products to a vehicle under warranty carries some liability on your part.
This isn't directly related to me any sort of way but,this gets old quickly on these forums.


All my life working on cars,race cars etc. Not one time have I experienced an oil related engine failure. I've recommended friends and family oil choices over and over again. Just because there's no "API" symbol on the quart bottles means nothing to me and never will worry about it.
 
This isn't directly related to me any sort of way but,this gets old quickly on these forums.


All my life working on cars,race cars etc. Not one time have I experienced an oil related engine failure. I've recommended friends and family oil choices over and over again. Just because there's no "API" symbol on the quart bottles means nothing to me and never will worry about it.
The same people that wait till warantee is up to run an "unapproved" oil are the same ones that say "manufacturers only spec an oil thick enough for the engine to make it just beyond warantee"
 
The same people that wait till warantee is up to run an "unapproved" oil are the same ones that say "manufacturers only spec an oil thick enough for the engine to make it just beyond warantee"
The same people who love giving unsolicited and unnecessary advice. Remember the "MDS Crowd"?
 
Let's break this down even further. Mazda's OEM fill is a relabel of Idemitsu Zepro 5W-30. Here's their published specs.

288806799_536163854951870_587398008685738052_n.png


The specs for High Performance Lubricants PCMO 10W-20 can be found here....


HPL PCMO 10W-20.jpg


Now let's put the 2 of them side by side, looking at the critical factors at play here.

Mazda 5W-30 vs HPL 10W-20.jpg


The difference in KV100 is
I also didn't make this decision solely. I consulted 2 very knowledgeable people, neither one associated with HPL and both given only the specs for both oils without brands, and they agreed that my decision was sound. I presented the information to the owner, noted the grade was outside of warranty spec, and he acknowledged it.

Obviously the engine is doing just fine per the UOA. He's happy with the choice and wants to keep using it.

 
I did calculate it. It gave me the same result as the spreadsheet.

Redline HP 5W-30 = 2.84 cP

It's also worth noting that Redline HP 5W-20 is 2.65 cP. Some of the 5W-30 oils in the spreadsheet have an HTFS of
Here's the spreadsheet from Google Docs.


*PPPP 5W30 KV100 looks off (I'm guessing should be 9.6 instead of 8.6 ?
 
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