GrantG

It’ll come to US. I think Ukraine is only where the oil is coming from - this info does not only apply to Ukrainian Porsche market…

GrantG

Can’t remember where the thread is, but someone analyzed the oil between each of several quick oil changes (done a few minutes apart) and the oil only resembled new oil after the fourth change. With the new green color, it will be easier to see when the stuff coming out begins to look fairly new.

Best case scenario, Porsche prescribes a procedure for dumping all the previous oil. Otherwise, some people will be content with half new and half old oil and the rest of us crazy OCD guys will need lots of new oil

GrantG

That’s in liters, btw. Not huge difference, but a little

mthreat

lol I just bought like 10 quarts of the C40 ESP stuff from Autozone on sale.

GrantG

I have a bunch too. I’m giving mine to a friend with a GT4, but you may be able to return it…

4carl

I’ve got about 12 quarts also. Luckily, my GTS takes the same oil.

mthreat

I'm confused by the article. First it says:

Applications:
...
* 911 GT3 RS (991 and newer)

Then just below, it says:

Mobil 1 C40 GT 0W-40 is not suitable for Porsche vehicles requiring an A40, C20, C30 or C40 approved Mobil 1 engine oils.

Since the 992 GT3 RS calls for C40 oil, does this mean it isn't suitable? Or since a 992 GT3 RS is a "911 GT3 RS (991 and newer)", is it suitable?

EMdoc

Haha my thoughts exactly. Unless my critical reading skills are lacking. Confused as well.

GrantG

I think the answer is cars like the 991 GT3 (A40) and 992 GT3 (C40) are going to be re-designated as C40 GT. Supposedly this week (Feb 1st), according to first post in this thread.

EMdoc

Question...if I need to add some oil over the next 8 months until the first oil change, I think I continue to use the quart of C40 I already have? I've added 150ml in the first 400 miles since getting the car (level is now at 75% of the "max" bar). Maybe the first oil change will involve the new designation/formulation at the dealer?

GrantG

You may as well top-up with whatever’s in the car now.

EMdoc

Thanks!

4carl

I did look at the technical specifications for both oils.
HTHS which stands for high temperature high stress .
It is a rating that test the ability of oil to maintain its film strength both oils were 3.8.
I also looked at the velocity index, the higher, the number the better it’s the ability of the oil to maintain its viscosity through various temperature ranges.
The regular C-40 actually has a higher viscosity index than the new oil, not much but it is higher.

Obviously, there must be more to it than this because everything that I can find on these two motor oils shows their performances about the same.
The one thing I couldn’t find is the zinc content on both oils racing oils can go up to 1300 street legal oils are 6– 800 I believe.
I would think if it was anything that was detrimental to the longevity of the engine there would’ve been some type of update from the factory?
It would be in their best interest to be proactive Because it will save them a ton of money

WenigerAberBeser

C40 GT … you mean C40 Greta Thumbutt? Is it a new oil to be friendly to the jellyfish?

Indyxc

It's interesting, after a 2nd look, it might be a rebanding of an updated formula the current Mobil 1 ESP X3. Both oils are HTHS of 3.8, but as you noted the viscocity index of 40 GT is lower at 199 vs 204 for Mobil 1 ESP X3.

Generally, higher VI means a better base oil, this new 40 GT oil, unless it has a ton of ZDDP additives and moly, on paper does not look impressive

Mobil 1 ESP X3 spec sheet for reference:
https://www.mobil.com/en-be/passenge...1-esp-x3-0w-40