Porsche Approved Oil: replacement of A40 with C40 oil

[95892A]

Understood that A40 oil cannot be used on new Porsches with sensitive exhaust particle filters

When C40 oil outperforms A40 in several ways, then why is C40 oil not backwards compatible with vehicles that require A40?

What would the bad result be if C40 oil were poured in an engine that needed A40 oil?

Strange finding: Ravenol RUP 5W40 has C40 approval and is also recommended for A40

Anyone can explain this?

 

[BMW Dom]

Welcome! I’m too tired to answer right now . But there are some very knowledgeable people here

 

[oggb]

C40 approval and is also recommended for A40

"recommended for" =/= approved/licensed for use in _________
Maybe it meets the reqs of A40, maybe not.

It's kind of like Valvoline Maxlife ATF is recommended for every transmission known to man. If aliens came to Earth and their UFO was leaking a mysterious red fluid that smelled like old fish bait MaxLife would change their labeling to "recommended for UAVs" or whatever the new word is.

 

[BMW Dom]

"recommended for" =/= approved/licensed for use in _________
Maybe it meets the reqs of A40, maybe not.

It's kind of like Valvoline Maxlife ATF is recommended for every transmission known to man. If aliens came to Earth and their UFO was leaking a mysterious red fluid that smelled like old fish bait MaxLife would change their labeling to "recommended for UAVs" or whatever the new word is.

You must know a lot about transmission fluid. Why is every company recommending their ATF for many of the same applications?

 

[930.engineering]

Strange finding: Ravenol RUP 5W40 has C40 approval and is also recommended for A40

Even more strange, Ravenol RUP had A40 before and VW 511 00 simultaneously.
I pointed out this oddity some time ago.
Just guessing, Porsche doesn't see any need to allow C40 for older engines and
I have to admit this intention would be legit. There's still much more choice on
Porsche A40 approved oils than there is on C40 approved oils. I don't have that
list on hand, but I'd bet it's a short one.

.

 

[2EHA]

A40 doesn’t have a forced TBN minimum like A3/B4. there’s nothing stopping a high performing C40 from passing A40

the era of mega TBN flagship oils is coming to an end

 

[tundraotto]

When C40 oil outperforms A40 in several ways,

This caught my attention - in what several ways does C40 outperform A40?

 

[edyvw]

Even more strange, Ravenol RUP had A40 before and VW 511 00 simultaneously.
I pointed out this oddity some time ago.
Just guessing, Porsche doesn't see any need to allow C40 for older engines and
I have to admit this intention would be legit. There's still much more choice on
Porsche A40 approved oils than there is on C40 approved oils. I don't have that
list on hand, but I'd bet it's a short one.

.

It is not oddity. Old VW502.00 has low TBN minimum as well as A40. So in practice, oil could be approved for both. My guestimate why A40 is strictly used in older engines is fuel dilution.

 

[edyvw]

This caught my attention - in what several ways does C40 outperform A40?

C40 has higher deposit and emissions protection requirements. As for pure protection, both have same test sequences.

 

[UncleDave]

This caught my attention - in what several ways does C40 outperform A40?

The lubrizol spider chart does a good job here.

Relative Performance Comparison Tool for Passenger Car Specifications - Engine Oil Additives - The Lubrizol Corporation

online.lubrizol.com

 

[tundraotto]

The lubrizol spider chart does a good job here.

Relative Performance Comparison Tool for Passenger Car Specifications - Engine Oil Additives - The Lubrizol Corporation

online.lubrizol.com

Already looked at it - and the requirements look like the HTHS spec is the same 3.5 or above - but the C40 has limits on anti-wear additives for exhaust aftertreatment longevity purposes.

 

[edyvw]

Already looked at it - and the requirements look like the HTHS spec is the same 3.5 or above - but the C40 has limits on anti-wear additives for exhaust aftertreatment longevity purposes.

I just got back from Bosnia. My brother found 2004 Mercedes E220 cdi for cheap and got it just because. Has 367,000 miles using these ACEA C3 oils with lower-SAPS. Still hits some 220km/h on the highway.
So, do not worry about anti-wear additives. The question is: which anti-wear additives? Do not forget, A40 and C40 have to pass same performance testing.

 

[95892A]

It is not oddity. Old VW502.00 has low TBN minimum as well as A40. So in practice, oil could be approved for both. My guestimate why A40 is strictly used in older engines is fuel dilution.

Do you mean A40 has less fuel dilution issue than C40 or older Porsche models engine have more serious fuel dilution issue than newer Porsche models engine?

 

[edyvw]

Do you mean A40 has less fuel dilution issue than C40 or older Porsche models engine have more serious fuel dilution issue than newer Porsche models engine?

Older engines have more fuel dilution issues. You want higher TBN oil.

 

[tundraotto]

Older engines have more fuel dilution issues. You want higher TBN oil.

Which ones have a higher TBN - Porsche A40 or C40 oils?

PS.... Your bros' MB E220 CDI is a diesel - so it uses a different spec oil.....

MB 229.5 is about the most stringent spec available from gas engines and is in kind of line with Porsche A40 - lots of similarities.

 

[edyvw]

Which ones have a higher TBN - Porsche A40 or C40 oils?

PS.... Your bros' MB E220 CDI is a diesel - so it uses a different spec oil.....

MB 229.5 is about the most stringent spec available from gas engines and is in kind of line with Porsche A40 - lots of similarities.

That is really not how it works.
A40 is full SAPS oil.
in EU gasoline vehicles use low-SAPS oils since 2009. MB229.51 is used in MB gasoline engines there since 2009. You have numerous topics about this subject. And, no A40 is not as stringent as MB229.5. In certain aspects it is, mostly oil’s track performance.

 

[95892A]

Older engines have more fuel dilution issues. You want higher TBN oil.

Do you think I can use C40 to replace A40 if OCI can be done shorter, say 5000km instead of 8000-10000km?

I wonder both Red Line 0W40 and Euro Series 5W40 have A40 approval but their TBN values are 7.54 and 7.2 respectively.
And many oils with both A40 approval and ACEA C3 have even lower TBN values such as:
Addinol Premium 0540 : 6.37 and Valvoline SynPower MST C3: 7

 

[edyvw]

Do you think I can use C40 to replace A40 if OCI can be done shorter, say 5000km instead of 8000-10000km?

I wonder both Red Line 0W40 and Euro Series 5W40 have A40 approval but their TBN values are 7.54 and 7.2 respectively.
And many oils with both A40 approval and ACEA C3 have even lower TBN values such as:
Addinol Premium 0540 : 6.37 and Valvoline SynPower MST C3: 7

Redline Performance is not approved for anything. You can cut OCI and check. C40 will be good for at least 7,500km.

 

[95892A]

Redline Performance is not approved for anything. You can cut OCI and check. C40 will be good for at least 7,500km.

Yup, You are correct that Reline only recommends for A40 only, no approval.

 

[Bjornviken]

Mobil1 x3 ESP 0w-40 (C40 )is not backwards compatible with vehicles that require A40, C30,or C20. So i think its hard to know what is behind this