Porsche GT3 /RS A40 Oil

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Indyxc

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Hello all,

Great forum, I've visited back and forth over the years looking for regular oils for regular cars. Finally got my dream car (Porsche 2016 GT3 RS) and looking for the best oil, which seems more compliccated on the 2016 991.1 GT3 RS, and GT3 as they have finger follower wear issues, between the finger follower and the cam shaft. The finger follower wears, and sends material into the engine, and then requires a engine replacement (expensive). The GT3 is under a 10 year warranty from Porsche, the GT3 RS is NOT, even though they have the same finger follower, but other changes that are suppose to "fix" the issue. Not all units affects, just the ones with inclusions in the finger follower.

The factory spec'd oil is Mobil 1 FS Euro 0w-40. Concensus is it's a fine oil, but Mobil paid Porsche to spec it, and the finger follower wear benefits are from oils that have high ZDDP, especially Zinc. Likewise, there is a belief oils with higher viscosity do better as at high rpms on the cam the oil is better retained, and not wiped away by the high forces between the finger follower and cam.

So the search is on a oil with high viscosity and high zinc that is A40 spec'd.

Mobil 1 Options:
1. 0w40 FS Euro- Factory
2. 5w40 FS Euro- Factory, but higher visosity?
3. 5W50 FS X2 Euro- $$$ Even high visosity?

Motul:
1. Motul 8100 Gen 1 5W40- Recomended by Porsche Folks due to Higher Viscocsity, and High Zinc-> I think my first choice.

Amsoil
1. Amsoil Euro 5w40- Recomended for both higher Visc, and Higher Zinc. I can't seem to find a virgin oil analysis.

Liquid Moly
1. Liquid Moly HT 5w40 with Ceratec- Good Visc, but Zinc is marginal.

Attached is an oil analysis compiled on the Porsche Forum, all oils minus Mobil 5w40/50, and Amsoil Euro.

DT oils are not A40 spec'd so not really one I want.

What say y'all? This is for a garage queen that won't start in an ambient in less than 45F.

Thanks!
1698112232534.jpg
 
One thing, it’s a Porsche approval not a “spec” so any oil with the approval has paid for the approval not just ExxonMobil.

And any viscosity difference within the same grade isn’t going to be meaningful. You’d need the 50-grade to make any difference.

If you want to use an oil with A40 approval none of the ones you list will be meaningfully better or worse regardless of what we you’ve read.
 
It's the phosphorous that's the AW component of ZDDP, not the zinc.

M1 0W-40 has a fair amount of phosphorous already (~930ppm), which is much higher than what we see with the basic ILSAC oils for North American applications.

Mobil and Porsche have an R&D agreement, just like Mobil has with GM (Corvette) and with Mercedes-AMG. Mobil doesn't pay Porsche to make the oil the factory fill, they have a partnership and that's simply one of the byproducts of the arrangement.

Also, a quick glance at those UOA's, the Motul 8100 isn't any heavier than the M1 0W-40. The Driven DT40 does appear to be heavier.
 
OVERKILL said:
Mobil and Porsche have an R&D agreement, just like Mobil has with GM (Corvette) and with Mercedes-AMG. Mobil doesn't pay Porsche to make the oil the factory fill, they have a partnership and that's simply one of the byproducts of the arrangement.
Click to expand...
Yes a marketing agreement completely separate and unrelated to the specifics of the approval.
 
If straying from approvals I would probably run DT40/DI40, 300V 5W-40, HPL BAS or something like that in this engine.

If staying with A40 I’d probably run M1 X2 5w-50 or the Motul 8100 XCess Gen 2 as 2nd choice. The updated SP Motul has lower VI and the HTHS is a bit higher than M1 0W-40 most likely (est 3.6).

I would just say that high ZDDP does not necessarily mean lower cam wear. I somehow doubt Motul 300V is compromising valvetrain wear protection compared to a more pedestrian full SAPS oil.
 
ZDDP is a chemical compound, as shown in the attached screen shot, but the test to identify the zinc and phosphorus is by the concentration of each element showing up separately. You’ll notice in all the tests there is slightly more zinc than phosphorus and if you want to divide the zinc concentration by the phosphorus concentration you’ll get a ratio slightly larger than 1. Statistically the difference is not significant and looking for a certain zinc or a certain phosphorus concentration is probably a waste of time. Having said that, a person is free to spend all the time they want on it. What does the wear scar on Project Farm say? LOL

2A4C8813-1D13-462B-984B-75B630FE2217.png
 
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Have a bunch of guys in my club with GT3s.....they all run redline 0w40, Motul Sport 5w40, or the Motul 300v 5w40. All cars are tracked hard. 1 engine was pulled for a rebuild due to a headgasket issue/overheating but the valve train had no signs of wear. 27k on the clock. All these oils have a HTHS of 4. I wouldn't go below that.
 
Indyxc said:
Hello all,

Great forum, I've visited back and forth over the years looking for regular oils for regular cars. Finally got my dream car (Porsche 2016 GT3 RS) and looking for the best oil, which seems more compliccated on the 2016 991.1 GT3 RS, and GT3 as they have finger follower wear issues, between the finger follower and the cam shaft. The finger follower wears, and sends material into the engine, and then requires a engine replacement (expensive). The GT3 is under a 10 year warranty from Porsche, the GT3 RS is NOT, even though they have the same finger follower, but other changes that are suppose to "fix" the issue. Not all units affects, just the ones with inclusions in the finger follower.

The factory spec'd oil is Mobil 1 FS Euro 0w-40. Concensus is it's a fine oil, but Mobil paid Porsche to spec it, and the finger follower wear benefits are from oils that have high ZDDP, especially Zinc. Likewise, there is a belief oils with higher viscosity do better as at high rpms on the cam the oil is better retained, and not wiped away by the high forces between the finger follower and cam.

So the search is on a oil with high viscosity and high zinc that is A40 spec'd.

Mobil 1 Options:
1. 0w40 FS Euro- Factory
2. 5w40 FS Euro- Factory, but higher visosity?
3. 5W50 FS X2 Euro- $$$ Even high visosity?

Motul:
1. Motul 8100 Gen 1 5W40- Recomended by Porsche Folks due to Higher Viscocsity, and High Zinc-> I think my first choice.

Amsoil
1. Amsoil Euro 5w40- Recomended for both higher Visc, and Higher Zinc. I can't seem to find a virgin oil analysis.

Liquid Moly
1. Liquid Moly HT 5w40 with Ceratec- Good Visc, but Zinc is marginal.

Attached is an oil analysis compiled on the Porsche Forum, all oils minus Mobil 5w40/50, and Amsoil Euro.

DT oils are not A40 spec'd so not really one I want.

What say y'all? This is for a garage queen that won't start in an ambient in less than 45F.

Thanks!
View attachment 184919
Click to expand...
Just to top off the above comments not all ZDDP is the same and as you can see from the UOA database which you posted there is no statistically significant difference in wear across all of the oils used.

Engineering and materials failures can't be solved with choice of oil.
 
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We've raced 3 Porsche cup cars over the years, we're currently racing a 991.1 Cup. I use Motul 300V 5w40 or Redline 5w40. Ester based oils have served us well and all the motors have been in terrific shape even past 100 racing hours. Motul 300V should probably not be run more than 5000 miles in a street car as it has less detergents. We change it at 10-12 hours in race motors and the UOA's look terrific, could go double that I imagine.
 
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