How can you know the micron rating on oil filter if it is not written?

Answer 1

You could search on Google for "Oil Filter Reviews". But to be honest you do not need to know this. Just use a quality filter such as Purolator, Wix, AC/Delco, and you will have good protection. Avoid Fram, STP, and Super Tech. And do not fall for the 3,000 mile oil change myth. The 3000 mile oil change interval has been pounded into people's heads for decades. It had a scientific basis when engines used non-multi-weight, non-detergent oil. It no longer has any scientific basis, but it is still being promoted by certain entities, most notably the oil change industry in the United States. This myth is also sometimes known as the "Cheap Insurance Myth." There are still vehicles that need 3K oil changes, but it's not because the oil goes bad after 3K miles. One example is the Saturn S series. These vehicles have a timing chain system that is very sensitive to clean oil because oil pressure is used as hydraulic fluid to ratchet up the timing chain tensioner. If varnish forms in the timing chain tensioner bore then this system can fail and the chain will become loose and eventually break. It is a waste of money and oil to change your oil every 3,000 miles unless you drive a car such as the Saturn. You can easily change your oil every 5,000 miles under severe conditions and 7,000 miles under normal conditions and be fully protected. Change the filter at every oil change. Also in my opinion using a synthetic oil is a waste of money unless you are operating your vehicle in an extremely cold climate or racing your vehicle. Some vehicles such as Corvette require synthetic and it should be used, but for the average car, it is a waste of money.I must ammend my answer as of 2/13: Many new cars require the use of 0w-20 weight oil. As this weight is not produced in a conventional oil you will have to use a Synthetic oil in order to use the correct weight. By all means do so.