What Do Engine Oil Codes Mean?

The engine oil is considered as our car’s lifeblood. In order for our internal combustion engines to run smoothly and efficiently, it needs to be well lubricated. Thus, it is but essential for us to always check and make sure that our beloved vehicles are running with a high-grade quality one. Topping it up and changing it religiously will help us keep our cars for a longer period of time and save money as well.

But letting a professional mechanic change the oil for you isn’t just the only task. You also have to make sure that the kind of oil he puts in your car is true of top quality. So how will you know that? How will you know that the car oil you’re buying is of quality if in the first place you can’t seem to understand the codes placed in its packaging?

As trusted cash for cars and car removal Melbourne company, and as automotive experts who have been in the industry for two decades, we are here to give you a much simpler and clearer explanation about those complicated engine oil codes:

The engine oil codes are established by the SAE (Society of Automotive Engineering). They developed a numerical code system to grade and categorize oils according to their viscosity. In simpler terms, the oil’s thickness and weight, which will then create a resistance to flow or movement.

There are two kinds of motor oils: the SINGLE GRADE and the MULTI-GRADE. Most of the cars we use today are multi-grade oils. Those single grade oils (also known as “straight weight oils”) are usually marked with just one number. The higher it is, the thicker the oil.

Codes for Viscosity

For the multi-grade ones, because they are made to protect the engine across a wide range of operating temperatures. Their codes are consist of two parts normally separated by a dash. Let’s take for example the 10W-40.  The first part, the one with a ‘W’ indicates the oil viscosity is low temperatures; because W is for winter. The second part, which is only a number, shows how thick the oil is at the engine’s regular operating temperature. When you look at the one with a W, it must be at a lower number (especially if you live in an area where it has mostly cold weather). If the oil is too thick during winter, it won’t definitely flow and circulate easily in your engine. They say 5W or 10W are some of the best. It still depends on the weather conditions in your area. For the second number, prefer a higher one. Because if the oil’s too thin or flowier when the engine is hot, it won’t be able to protect and lubricate well. Your car will be less efficient.

Codes for specifications

To further help you in picking out the correct oil for your car, oil specs are also marked on their labels through codes. They should tell you what that particular oil is most suitable for; also, if it is for the engine’s cleanliness, strength, heat resistance, etc. Here are some of the oll specification systems:

  1. API (American Petroleum Institute) – provides oil specifications by classifying them in a code that consists of two letters. The first letter is going to be either an S or a C. ‘S’ stands for service; meaning it’s for service and passenger vehicles that run on petrol. The ‘C’ stands for commercial vehicles running on diesel engines. Then, the second letter signifies the quality standard. If it’s farther along with the alphabet, it means it is of better quality. Thus, SL is better than SA.
  2. ILSAC (International Lubricants Standardization and Approval Committee) – they grade the oils and come up with codes that also has two parts. The latest one is ILSAF GF-5. If the second part or the number is much higher, it means that oil is newer and will do a better performance.
  3. ACEA (Association des Constructeurs Européens d’Automobiles) – they govern specifications for engine oils for European cars. Their code just consists of 2 characters, the first one is a letter, the 2nd one is a number. A means it’s for petrol, B is for diesel, C is for both petrol and (light-duty) diesel vehicles that are catalyst compatible.
  4. OEM – motor oils also have specifications that adhere to their Original Equipment Manufacturer’s standards. Some carmakers really just have their own set of oil requirements for their cars’ engines. Some of the most common are VW, MB, and BMW.

As in the case of picking out your car’s motor oil, the saying “you get what you pay for” is technically applicable. When you buy cheap oil, you’ll most definitely get one with cheaper ingredients; thus providing poorer performance. Being in the car removal and sell my car Melbourne market for too long, we don’t expect everyone to be just like car enthusiasts. However, it does pay to know if you understand a thing or two about engine oil. It’s so comforting to know that because you know what those codes mean. No salesman or mechanic could ever fool you whenever you’re about to do an oil change. Still, the remains, that the correct type of oil you have in your engine plays a great part in keeping your car’s health.