Mobil 1 5&10W-30 are rated ACEA A1. Mobil 1 0w-40 is rated ACEA A3 which is suppose to be a higher rating. Why do the UOA of the 10w-30 show lower ware numbers than the higher rated 0w-40??
A3 doesn't have a fuel economy requirement and allows for 0.2% more sulfated ash max limit. Other than that, A3 ratings are superior to A1, and nothing says that an A3 oil can't have the fuel economy rating and the lower sulfated ash of A1 or A5. Look at 1.2, 1.3, 1.4, 2.1, pages 5 & 6 of http://www.acea.be/ACEA/20020618PublicationsOilSequences.pdfquote:
Originally posted by Jay:
ACEA A3 is not a "higher" rating than ACEA A1. It's a different rating. The two categories have different criteria that are mutually exclusive of each other. That is, an oil can't own ACEA A3 and A1.
The only differences between A3 and A5 are the HT/HS numbers and the fuel economy requirement (if I remember correctly.)quote:
Originally posted by Ken2:
A3 doesn't have a fuel economy requirement and allows for 0.2% more sulfated ash max limit. Other than that, A3 ratings are superior to A1, and nothing says that an A3 oil can't have the fuel economy rating and the lower sulfated ash of A1 or A5. Look at 1.2, 1.3, 1.4, 2.1, pages 5 & 6 of http://www.acea.be/ACEA/20020618PublicationsOilSequences.pdfquote:
Originally posted by Jay:
ACEA A3 is not a "higher" rating than ACEA A1. It's a different rating. The two categories have different criteria that are mutually exclusive of each other. That is, an oil can't own ACEA A3 and A1.
Ken
No. A1 oils can have a max HT/HS of 3.5, while A3 oils have to have an HT/HS of >3.5.quote:
Originally posted by TR3-2001SE:
Then this would mean an oil could have an A1 rating and an A3 rating???