On selecting the right motor oil

Jerome NeriAtty. Jerome G. Neri
The Scrutineer

AS CAR manufacturers become more environmentally conscious and are designing less polluting and more fuel efficient engines, oil requirements of the engines are changing fast. Understanding what is written in the oil container is very important.

The two major and indispensable things to look out for in choosing a motor oil for your car are the Society of Automotive Engineers (SAE) viscosity rating and the specification of the oil as rated by the American Petroleum Institute (API) and/or the Association des Constructeurs Européens d’Automobiles (ACEA).

OIL STANDARDS. This is a shot of an oil container showing the SAE viscosity grade and the relevant API and ACEA standards.
OIL STANDARDS. This is a shot of an oil container showing the SAE viscosity grade and the relevant API and ACEA standards.

The rule is that always use the type of oil recommended by the manufacturer of your car. The recommended oil can be found in the service manual of your car. I say recommended by the manufacturer because there are instances where the car dealer recommends oil different from that in the service manual for your car, and the reason for this is that an oil company has given this car dealer a good deal on oil sales.

The most common mistake of individuals, shops and even some car dealers is that they only look at the SAE viscosity specification and only think of motor oils as either mineral or synthetic, where oil change periods are less frequent when synthetics are used. Little do they realize that modern engines are built to tighter and more precise tolerances that the lubrication requirements have changed. New engines now require a more stable and temperature-resistant oil.

Thus, apart from the SAE viscosity, automobile manufacturers recommend an oil protection standard set by the API and/or the Association ACEA. These standards are found on the labels of the oil containers.

It is okay to mix different oil brands as long as it has the same SAE viscosity grade and the same API or ACEA rating.

Oil standards have been moving up at a rapid rate lately. The API, for example, has oil ratings from SA to SN, the latter being the latest. API ratings from SA to SH is now obsolete. The lowest API certified oil available in the market today is SJ, which is suitable for cars 2001 and below. SL is for cars 2004 and below, SM is for cars 2010 and below, while SN, the highest rating, is for cars 2011 and below. This illustrates that the newer rated oils are compatible with older engines, but the older rated oils are not compatible with newer engines. Therefore, it will always be best to get the highest grade oil no matter what car you have. For the ACEA ratings, it would be advisable to stick with A3/B4, A3/B3, A5/B5 and C3.

We have so many oil brands in the Philippine market today. Many of them have their own claims on how good their product is. There are normal to outrageous claims. These claims are never as reliable as the real scientific ratings. You would rather trust a person who claims to be smart and has good grades than one who claims to be smart and has no grades.
As for diesel engines, the current API ratings are CH-4, CI-4 and CJ-4, with CJ-4 being the most current. CH-4 are for 1998 or older, CI-4 for 2004 or older, and CJ-4 2010 or older.

In sum, when you select your oil, the brand does not really matter. What matters is that you choose oil with the correct SAE Viscosity and the correct API and/or ACEA ratings. The correct specs are found in your car’s service/owner’s manual.

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