The API rating is not that important... the basis of using a specific oil is the contents of the oil...
the higher API rating you go like CI-4 plus or CJ, the lesser the anti wear additive becomes because it follows the specification to prolong catalytic life and other emission control system... which is detrimental to engine protection and life...

Guys, just a personal note.. fake filters are not the only problem we have, there are a lot of fake and recycled oils.... I have sources in the lubricant industry that confirmed there are indeed recycled oils mixed with new oils especially in pails and drums and some other retail packaging of oils...

there are mixing plants in malabon, valenzuela, bulacan (north areas) that conducts the recycling, bad thing is that some business people clean the garbage oils and mixed it with good oils, so beware if the offer is too low for prevailing market price...

remember base oils from around the world have a current price, and prevailing price... here in the Philippines, the average cost of base oil only is around 19,000 pesos, the remaining cost is for the additive and operational cost... therefore if any oil would be abnormally low in price meaning below 10% of the total prevailing price you should do homework and probing... its not worth sacrificing the fleet or the engines you have for a couple of bucks... initially it will run fine, but eventually after a couple of year equipment breakdown will happen...