Originally Posted By: OldEuroCarLover
What if it's an oil that has a certification like BMW LL-01 that, presumably, means the oil should stay within spec for the allotted OCI? That's what I meant when I said all other aspects being equal. What if it's a 0w30 and a 5w30 with the same certification? From what I understand about all of this so far, the Castrol Edge 0w40, with the LL-01 certification, should be much better overall than any 5w30 with the same certification. Thicker at operating temp and able to withstand sustained high RPMs, and thinner at winter temps for cold starts.
I guess I'm trying to wrap my head around BMW's reason for recommending 5w30 when they could easily recommend 0w40.
In the case of LL-01 BMW's requirement is an oil that meets that specification and the grade becomes irrelevant for all practical purposes. You'reobsessing focusing on the wrong thing, as long as the oil meets the minimum HTHS it will be functionally equivalent.
What if it's an oil that has a certification like BMW LL-01 that, presumably, means the oil should stay within spec for the allotted OCI? That's what I meant when I said all other aspects being equal. What if it's a 0w30 and a 5w30 with the same certification? From what I understand about all of this so far, the Castrol Edge 0w40, with the LL-01 certification, should be much better overall than any 5w30 with the same certification. Thicker at operating temp and able to withstand sustained high RPMs, and thinner at winter temps for cold starts.
I guess I'm trying to wrap my head around BMW's reason for recommending 5w30 when they could easily recommend 0w40.
In the case of LL-01 BMW's requirement is an oil that meets that specification and the grade becomes irrelevant for all practical purposes. You're