A car without an engine is just an ornament sitting in your front yard but an engine without lubrication is just a disaster waiting to happen. So, what is it that makes an engine oil crucial as to how an engine operates? Why are there many specifications to an oil, especially when they practically do the exact same thing? We’re kicking off a technical segment called ‘CARS101’ where we take deep dives into how cars actually work. In case you haven’t noticed, our ‘MODS101’ series on YouTube follows a similar concept as we take an old Proton Satria GTI and show you how to modify a car the correct and safe way without breaking the bank. That being said, cars aren’t too complex when you take away all of the electrical bits and bobs. To simplify the whole system, it’s just converting one form of energy into another. However, with engine oils, there are a lot of factors to consider upon purchase which depend on the consumer itself. Whether you’re getting the off-the-shelf oil at your local supermarket or a premium specialised formula that can only be bought from a handful of people in the country, they have special characteristics that may or may not be fitting for your engine. This article is rather detailed and may require some time for you to go through the details but hopefully it benefits you to be a smart consumer.
What does an engine oil do?An engine oil works as a form of lubrication in the engine, the thin film of oil is what keeps the metal components such as pistons from grinding the cylinder walls, leaving scoring marks that would make Freddy Krueger jealous. Engine oils are made to reduce friction and wear of an engine, while at the same time, cleans the engine as well. It too works as a way to keep an engine cooled as the heat from the components are transferred to the oil and out of the system. Fun fact: What we know as engine oil today was initially ideated to be a medicinal product based on crude oil as it was tested for healing properties. However, it did not bear any medicinal properties but it showed great lubricating properties and it worked very well at high temperatures. Hence, it was then used on steam engines and the rest is history.
How Do I Choose An Engine Oil For My Car?Most consumers choose their engine oil based on either brands, price or just availability. However, there are quite a lot of factors you should consider upon getting yourself a bottle of the golden fluid. Especially in Malaysia, there have been multiple reports of 'fake' engine oils that have been stamped with all of the iconic brands. Hence, buying a bottle of engine oil on online shopping platforms may not be the wisest choice. First of all, for you to choose a bottle of engine oil for your car, you have to make sure that the viscosity is appropriate for your engine. A different viscosity may make the engine feel rather lethargic or even worse, cause internal damage. Whenever you get yourself a bottle, refer to the owner's manual or consult a trusted and reliable mechanic just in case. While viscosity should be referred, the grade of the oil however is completely up to you. Going back to the authenticity of engine oils, make sure you get your engine oil from a trusted dealer. You can contact the brand directly to find a dealer closest to you if you are worried. Just don't be tempted to pull the trigger on very cheap and under market value fully-synthetic oils as they may actually be fake goods. While these are still oil nonetheless, their source is unknown and may not have any properties that can protect your engine.
What Do The Things On The Bottle Mean?We’re gonna start with the basics first, the selection of engine oil. See, there are a lot of oils on the market with most having words such as “semi-synthetic” or “mineral” but what do all these things mean? On the surface, they will all work in the engine BUT they will not work as efficient. Each engine has their own specific oil characteristics, so it truly depends on your owner’s manual which will state the recommended oil. For engine oils, there are quite a variety to choose from but in general, these three terms are often tossed around:-
- Mineral oil
Mineral OilMineral oil or conventional oil is often the cheapest product in the market as it is also the least refined of all engine oils. These are essentially refined petroleum oils that are treated to work under a wide range of temperatures. More often than not, these are regularly used on older vehicles as well as motorcycles. That being said, mineral oils are usually used up to 5000km as they offer little to no lubrication and protection against friction-induced heat. While high-heat makes them susceptible to breakdown, they also work inefficiently in colder temperatures. Hence, making them useful for a very short life span.
Semi-Synthetic OilThe semi-synthetic oil sits in between the mineral oil and fully-synthetic. These are also often called a ‘synthetic blend’. Sort of like the best of both worlds with the affordability of mineral oils but the near-similar benefits of fully synthetic oils. While this does sound like the most bang-for-buck option, that isn’t necessarily true. Semi-synthetic engine oils are cheap for a reason. The term ‘blend’ refers to the blend of synthetic and mineral oils. This is also the reason why they are able to keep the prices of these oils on the lower side of the price spectrum. However, it does give additional protection against wear in the engine. These will usually last for around 7000km. Fully-Synthetic Oil These oils are often the ones that you’d want to pour into your engine. They offer the best in protection as well as fuel economy. That being said, anything that is good will never be cheap. Synthetic oils have to go through rigorous treatment for it to break down to its molecular structure which removes all of its impurities. This makes fully synthetic oils superior to its counterparts as it maintains the molecular structure in either cold or hot temperatures. Ester-based engine oil is also classified in the fully synthetic oil category. These factors are why fully synthetic engine oils are often the most expensive options but it is also the reason why these oils can last for around 10000km.
What is SAE and the ‘W’ rating?Engine oils are graded by the SAE or Society of Automotive Engineers, a universally-recognised rating in which the oils are graded depending on the viscosity of the fluid. On the other hand, viscosity is the quantity which expresses the internal friction of such liquid. Another factor for different viscosities is also temperature as they differ from hot to cold. Oils that do not have an SAE rating will likely mean they are yet to be approved by the SAE. The ‘W’ in, let’s say, ‘5W-30’ is in fact the rating for cold climates or winter to be exact. It’s technically a gauge that tells you how the oil will flow in the winter. A lower ‘W’ number indicates a better cold flow. However, winter is irrelevant for us Malaysians and you should focus more on the numbers that follow the ‘W’. It generally works the same way, lower numbers indicate a smoother flow at operating temperature. A 5W-30 oil is engineered to behave as a 5 weight oil at the starting temperature and a 30 weight oil when the engine reaches its normal operating temperature.
“I’ve seen an SAE30 oil”, what is that?These are called monograde or straight-weight oils. The ones that are often seen such as the “5W-30” are generally classified as a multi-grade oil as it caters to the colder climates. But countries like us which are blessed with 30°C weather all year round can consider using monograde oils but they are usually tougher to source.
What is API and why do I see it on engine oil bottles?API or American Petroleum Institute are the ones who licenses these products after numerous testing to determine the performance level of the lubricants. While it may sound similar to SAE, it is completely different. If it has an API rating, it means that the product has been tested and been granted approval to use the API seal.
There Are Many Standards That Apply To Engine OilsWhile SAE and API are usually the ones seen on bottles, you may have also seen names like
- ILSAC (International Lubricant Standardization and Approval Committee)
- ACEA (Association des Constructeurs Européens d'Automobiles)
- JASO (Japanese Automotive Standards Organization)
- ASTM (American Society for Testing and Materials)
There Are Codes After The API, What Do They Mean?Maybe you saw a code such as 'SN' right after the API stamp on the bottle, this also indicates the targeted engines it is designed for. Codes can mean a lot things, such as:-
- SN: For vehicles manufactured after 2010
- SM: Vehicles manufactured between 2002-2009
- SJ: Vehicles manufactured before 2001
- CJ-4: Four stroke high speed diesels manufactured from 2010
- CI-4: For vehicles built between 2002 and 2010
- CH-4: Vehicles built between 1998 and 2002
Engine Oil Additives And What Do They Do?Engine oil additives are a bit of a debated topic among enthusiasts. Some swear by it and some will swear at you for using it. However, we’re not here to talk about whether these things actually function or not but rather the idea of what it is meant to do. Engine oil additives are basically vitamins for your car’s engine. While lubricants are already packed with additives from the refinery, additives are supplements to whatever the engine oil doesn’t have. Most engine oil additives claim to have protection against corrosion, removes contaminants, prevents sludge build-up and helps cool the engine. Different oil additives can be selected to enhance the desirable properties of a particular oil for specific applications. Among the oil additives that are offered are:-
- Anti-wear additives
- Corrosion and rust prevention
- Viscosity modifiers
Are Engine Oil Additives Required For My Car?Well if you’re driving an old car with high mileage, it may be best to give the engine a good treatment. Engine oil additives may actually restore some lost performance in the engine and further increase the longevity of the said engine. While it may not fix all the issues, it may however fix some of these issues:-
- Reduces wear and tear
- Restores compression
- Stabilizes engine oil
- Reduces heat
- Lowers noise
- Improves fuel consumption