I was expecting the HTHS to be above 4 if they would’ve added zinc, or any other wear reducing additives.

https://360.lubrizol.com/2019/How-is...HS%20viscosity.

 

Asked again for clarification and they said, the current oil formulation will be kept but rebranded with the GT designation, however the current C40 oil formula will change and become more environmental friendly (assumabky due to reduction or change of the wear protection additives) which is suitable for low friction roller cam follow as the current non Gt engines.
The gt engines need better wear protection due to direct cam to rocker contact.

So the new oil is the old oil just green. Due to the change in additivation the green gt oil has to be used with oil produced as of February.
No change in viscosity etc.

Still strange the half arsed oil change with 50% of oil remaining gin the engine.

 

Love this channel! Agree, really surpising a GT oil would be below 4.0. I am currently running Mobil 1 FS X2 5w50, hths 4.4. Changing to Driven DI40 next oil change, HTHS 4.2, but with higher moly, and ZZDP then FS X2.

 

from bard AI


The Mobil 1 oil that meets the Porsche C40 specification and has a 0W-40 viscosity is Mobil 1™ ESP 0W-40. However, the zinc level in this specific oil is around 600 ppm, which is lower than the other Mobil 1 0W-40 options I mentioned previously.While lower zinc content helps reduce emissions and friction, some Porsche owners, especially those with older models, prefer an oil with a higher zinc level for additional engine wear protection.

Here are some alternative options to consider for your Porsche C40:

• Mobil 1™ FS 0W-40: This oil has a 1,000 ppm zinc level and meets many Porsche specifications, although it may not be officially Porsche C40 certified. It's a good compromise between lower emissions and higher wear protection compared to Mobil 1 ESP 0W-40.
• Rotella T6 5W-40: This is a popular synthetic oil for high-performance engines and contains 1,500 ppm zinc. It is not officially Porsche C40 certified, but many Porsche owners use it successfully. However, it's a 5W-40 oil, which means it may not be as thin at cold temperatures as a 0W-40 oil, potentially affecting cold-start lubrication.

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Thank you! I'll keep the 13 quarts I have of the ESP X3 then

But this also means that cars like the 991 GT3 will be changing from A40 to C40 (ESP X3, now C40 GT)? Still a bit confusing...

 

Old rules of thumb do not fully apply to modern oils and engines. For example, oil that loses more viscosity when heated up is usually worse and it will also have lower HTHS; and drop in HTHS for the same oil with use means oil is losing its strength. This created a perception that low HTHS is bad. But in general oil with lower HTHS by design is not always worse. Modern formulations can have both lower viscosity and stronger film. Similarly with Zinc - it's an effective and cheap way to increase protection in high-temp and high-load areas but it's not the only way anymore. Also, zinc additives work by attaching themselves to metals and forming a sacrificial layer that repeatedly wears out and gets re-formed. But in modern engines more and more high-load friction surfaces are NOT metal but rather aluminum oxide or even diamond-like carbon coating. These are not metal and do not attract zinc as metals do, for such engines zinc may be less effective than other means of strengthening the film.

But yeah, environmental regulations making it harder and harder to make good oils. First zinc, now EU is pushing for sub-3 HTHS in oils by 2025, so maybe that's why we are seeing this need for special oils for some engines.

 

they have a 90 day return policy.
I just returned 12 quarts today.....

 

So, I appreciate your efforts to figure this out. But, the numbers don't support this conclusion. If you check the specifications for the new GT oil and compare to the previous ESP X3, they are not identical (which is what we'd expect if the information you received is accurate):

https://www.mobil.com/en-be/passenge...1-esp-x3-0w-40

https://www.mobil.com/en-ua/passenge...1-c40-gt-0w-40

Check the Kinematic Viscosity @ 100 C, mm2/s, ASTM D445 on both (13.8 on one and 14.1 on the other)

And Viscosity Index (199 on one and 204 on the other)

 

Will this initially be Mobil 1 as Well?

 

Initially and in perpetuity, if recent history is any guide (Mobil made the only required C40 0W40).

 

Well, that's annoying. I too also have a box of the ESP oil

 

The manual in the app was updated.

 

What version is that? Mine still lists the old oil.

 

I will be glad to take your worthless Mobil 1ESP off your hands.

Peter

 

Seems like people go crazy for oil dye. Well,I guess the marketing department at Royal Purple really know what they're doing...