Originally Posted by ZraHamilton
And yes, oils that meet ACEA A5/B5 are better because the European certification is harder to pass than just the API tests.
Pennzoil Platinum 5W-30, Mobil 1 5W-30, Mobil 1 High Mileage 5W-30, and Mobil 1 10W-30 are a few examples that have the A5/B5 certification.
ACEA A5/B5 may be generally better than some API and other rating, but not necessarily vs. A3/B3 or A3/B4. You may understand that, but I think John344 may have been asking if A5/B5 means better than A3/B3, for example. It does not; they are different specs for engines with different design needs. Example, comparing A5/B5 to A3/B4, the "5" In fact it has much lower HTHS range than A3/B4, and lower TBN number. It is designed to be energy conserving and sacrifices some HTHS for that goal. That's why I don't use an ACEA A5/B5, but rather the "tougher" A3/B4. It has an HTHS of 3.5 or higher, TBN 10.0+, and tougher wear limits than A3/B3 (same as A5/B5).
The ACEA ratings do not get "better" as the numbers get higher. Also, as newer specs are developed, new categories are not invented, but the year of adoption appended. For example, ACEA A3/B4-10 means the standards adopted in 2010. Now the spec is A3/B4-16.
This thread may help clarify it some too:
https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4048837/A3/B4_vs_A5/B5
Those of us who are "belts and suspenders" types wrt protection (as user SR5 describes in the last post of that thread I linked above) - we favor A3/B4. Others are keen for extreme cold weather start protection an A3/B4 can't readily provide, or others want the energy conserving ability it also can't maximize. So none of these ACEA ratings are superior to any others in ALL aspects. But they are WAY more robust certs than you find with the ones more common in North America.