[AlexC2er]

I’m planning a track day with my g42 m240i. I’m thinking of using castrol edge 5w40 (LL01) for track use and go back to 0w30 or 0w20 when I’m done. Should be fine, right? Or maybe it doesn’t get hot enough and 0w30 or 5w30 should be fine?

[oldbmwtech]

Originally Posted by AlexC2er

I’m planning a track day with my g42 m240i. I’m thinking of using castrol edge 5w40 (LL01) for track use and go back to 0w30 or 0w20 when I’m done. Should be fine, right? Or maybe it doesn’t get hot enough and 0w30 or 5w30 should be fine?

I tracked mine 5 weekends on factory oil before changing at my 1st. oil change. No issues. Coming up on my second oil change and so far 4 track weekends no issues. I'm letting the computer tell me when I need to change it or 1 year.

[RockCrusher]

My 2024 230xi owners manual allows for the use of 0w-20 or 0w-30 oil.

I would not use 0w-40 oil since the factory, at least AFAIK based on what is in my owners manual, does not sanction the use of a 0w-40 oil.

My info is Castrol is the source of the oil BMW uses.

So I might be ok using 0w-30 for track work. Maybe...

Castrol 0w-20:

Viscosity @ 100C: 8.13
Viscosity Index: 169
Flashpoint: 236C


Castrol 0w-30:

Viscosity @ 100C: 12.3
Viscosity Index: 205
Flashpoint: 196C

I say maybe because I recall years ago talking with the owner of a 993 Porsche (with the air-cooled engine) and his insistence in using 15w-50 oil which Porsche did *not* sanction for use in that engine instead of 0w-40 oil which is what Porsche did sanction.

The owner admitted with 15w-50 oil his track times were slower and on the street fuel mileage suffered a bit.

I'm not sure if a change from 0w-20 to 0w-30 would/could affect your track times or even affect fuel consumption on the street. But sometimes a "thicker" oil is not always the best oil.

But regardless of which oil you choose you should show up at the track with *fresh* oil in the engine. And have some extra bottles of oil in case the engine uses oil.

But with either 0w-20 or 0w-30 oil in the engine ideally you should monitor oil temperature and if it gets too high (>250F) take that as a clear sign the current track session is at an end. Take a cool down lap then pit. Let the engine idle some time to shed the heat load the engine has.

Also, be sure the brake fluid is fresh and the system properly flushed/bled.

[AlexC2er]

Originally Posted by RockCrusher

My 2024 230xi owners manual allows for the use of 0w-20 or 0w-30 oil.

I would not use 0w-40 oil since the factory, at least AFAIK based on what is in my owners manual, does not sanction the use of a 0w-40 oil.

My info is Castrol is the source of the oil BMW uses.

So I might be ok using 0w-30 for track work. Maybe...

Castrol 0w-20:

Viscosity @ 100C: 8.13
Viscosity Index: 169
Flashpoint: 236C


Castrol 0w-30:

Viscosity @ 100C: 12.3
Viscosity Index: 205
Flashpoint: 196C

I say maybe because I recall years ago talking with the owner of a 993 Porsche (with the air-cooled engine) and his insistence in using 15w-50 oil which Porsche did *not* sanction for use in that engine instead of 0w-40 oil which is what Porsche did sanction.

The owner admitted with 15w-50 oil his track times were slower and on the street fuel mileage suffered a bit.

I'm not sure if a change from 0w-20 to 0w-30 would/could affect your track times or even affect fuel consumption on the street. But sometimes a "thicker" oil is not always the best oil.

But regardless of which oil you choose you should show up at the track with *fresh* oil in the engine. And have some extra bottles of oil in case the engine uses oil.

But with either 0w-20 or 0w-30 oil in the engine ideally you should monitor oil temperature and if it gets too high (>250F) take that as a clear sign the current track session is at an end. Take a cool down lap then pit. Let the engine idle some time to shed the heat load the engine has.

Also, be sure the brake fluid is fresh and the system properly [...]

It’s not really about times. Ig more about that I can continuously track without oil temp through the roof. So I’m hoping a thicker oil will help with that. Maybe I’ll try with 0w30 to see how hot it gets

[RockCrusher]

Originally Posted by oldbmwtech

I tracked mine 5 weekends on factory oil before changing at my 1st. oil change. No issues. Coming up on my second oil change and so far 4 track weekends no issues. I'm letting the computer tell me when I need to change it or 1 year.

Had the oil changed in my 2024 230ix at around 600 miles.

Had a sample of the old oil and a sample of the virgin oil analyzed.

The old oil's viscosity was 7.3 at 100C; the virgin oil's viscosity was 8.5 at 100C.

[RockCrusher]

Originally Posted by AlexC2er

It’s not really about times. Ig more about that I can continuously track without oil temp through the roof. So I’m hoping a thicker oil will help with that. Maybe I’ll try with 0w30 to see how hot it gets

The takeway from the increase in lap times is the use of 15w-50 oil resulted in more engine friction. This additional friction can only raise the temperature of the oil. Thus with a thicker oil the oil temperature may be hotter than it would be with a thinner oil.

[chris719]

Originally Posted by RockCrusher

My 2024 230xi owners manual allows for the use of 0w-20 or 0w-30 oil.

I would not use 0w-40 oil since the factory, at least AFAIK based on what is in my owners manual, does not sanction the use of a 0w-40 oil.

My info is Castrol is the source of the oil BMW uses.

So I might be ok using 0w-30 for track work. Maybe...

Castrol 0w-20:

Viscosity @ 100C: 8.13
Viscosity Index: 169
Flashpoint: 236C


Castrol 0w-30:

Viscosity @ 100C: 12.3
Viscosity Index: 205
Flashpoint: 196C

KV100, VI, and flashpoint are actually not really important figures of merit for an oil if we are talking track use. HTHS viscosity is the most important metric as this defines how the oil behaves where it is actually needed. All of the manufacturer specs look at HTHS not the simple kinematic viscosity because HTHS correlates better with both wear protection and fuel economy.

The Castrol Edge Euro A3/B4 0W-30 has a HTHS of 3.5 cP as all LL01/LL04 oils must have at least 3.5 HTHS. It can be a 30 or 40 grade oil but the effective viscosity is about the same. For example, M1 0W-40 has an HTHS of 3.6 cP and thus is barely any thicker than the Castrol 0W-30. The 0W-20 and the BMW 0W-30 FE oils are significantly thinner, however, because they are around 2.7 cP HTHS for the 0W-20 and 3.1 cP for the 0W-30. I would personally never track my car with the 0W-20 and probably not even with the BMW LL01FE 0W-30. I would have no problem tracking the car with the Castrol 0W-30 that is 3.5 HTHS. There is a reason Porsche does not allow for <3.5 HTHS oils in the 911 and Cayman/Boxster still.

[AlexC2er]

Originally Posted by chris719

KV100, VI, and flashpoint are actually not really important figures of merit for an oil if we are talking track use. HTHS viscosity is the most important metric as this defines how the oil behaves where it is actually needed. All of the manufacturer specs look at HTHS not the simple kinematic viscosity because HTHS correlates better with both wear protection and fuel economy.

The Castrol Edge Euro A3/B4 0W-30 has a HTHS of 3.5 cP as all LL01/LL04 oils must have at least 3.5 HTHS. It can be a 30 or 40 grade oil but the effective viscosity is about the same. For example, M1 0W-40 has an HTHS of 3.6 cP and thus is barely any thicker than the Castrol 0W-30. The 0W-20 and the BMW 0W-30 FE oils are significantly thinner, however, because they are around 2.7 cP HTHS for the 0W-20 and 3.1 cP for the 0W-30. I would personally never track my car with the 0W-20 and probably not even with the BMW LL01FE 0W-30. I would have no problem tracking the car with the Castrol 0W-30 that is 3.5 HTHS. There is a reason Porsche does not allow for <3.5 HTHS oils in the 911 and Cayman/Boxster still.

The Castrol 0w30 just got ll01 fe certified, it’s still 3.5 HTHS I believe

[chris719]

Originally Posted by AlexC2er

The Castrol 0w30 just got ll01 fe certified, it’s still 3.5 HTHS I believe

Castrol prints Suitable For Use for LL01FE on the bottle. It's their own self proclamation, it doesn't carry official LL01FE approval, only LL01. LL01FE spec requirement is greater than 3.0 but less than 3.5.

[AlexC2er]

Originally Posted by chris719

Castrol prints Suitable For Use for LL01FE on the bottle. It's their own self proclamation, it doesn't carry official LL01FE approval, only LL01. LL01FE spec requirement is greater than 3.0 but less than 3.5.

Wait, so they’re saying it’s ll01fe even though it’s not actually?

[chris719]

Originally Posted by AlexC2er

Wait, so they’re saying it’s ll01fe even though it’s not actually?

This is a common game for oil companies. They use careful language and will say "recommended" for a certain spec but not approved. The Castrol bottle literally says LL01, SFU LL01FE. It's just Castrol's opinion. They are saying it's fine for LL01FE but it does not actually carry it.

[AlexC2er]

Originally Posted by chris719

This is a common game for oil companies. They use careful language and will say "recommended" for a certain spec but not approved. The Castrol bottle literally says LL01, SFU LL01FE. It's just Castrol's opinion. They are saying it's fine for LL01FE but it does not actually carry it.

That’s some word games. I gotta be careful now shopping for oil. Anyways, it should be fine for my b58.