An engine oil is generally, for a good reason, regarded to be the lifeblood of the engine itself. The engine, in equivalence to human anatomy, is analogous to our heart.
A car depends on its engine, and the engine depends on the regular use of high-quality engine oil. However, there are a lot of misconceptions about how this synergistic pair function and their roles to one another.
To clear the air a little, we’re going to shed a little light on the basics of engine oil to make you that much more of an informed consumer.
What is engine oil?
When mankind invented engines, they started realising that engines do not last because too much friction inside the engine results in premature wear. When they looked for a way to prolong engine life, where something could reduce friction and heat, they came out with engine oils.
The very first iteration of engine oil kept friction at bay on a steam engine, using a petroleum-based lubricant for the task.
As it lubricates engine components and reduces friction, engine oils also help to clean the engine by preventing contaminants from adhering to internal engine components. It also neutralises acids that originate from fuel and improves the sealing of piston rings and cools the engine by carrying heat away from moving parts.
What happens if I don't change my engine oil?
When engine oil is not changed for a long time, it will eventually turn into a gel or solidify, turning into sludge. When this happens, it will not be able to reach all parts of the engine, which could cause the engine to have accelerated wear of components and cause it to overheat and increase fuel consumption.
Eventually, the breakdown of the engine oil over time will lead to excessive wear due to the oil film being too weak to prevent metal-to-metal friction. Much like the unpredictability of a heart attack, this is the slow but sometimes sudden death of an engine.
How often should I change the engine oil?
Every car manufacturer has its own recommended engine oil change interval, but for best practice, we should change engine oil every few months or 5,000km to keep our engine in tip-top condition.
Some car brands stipulate engine oil changes every 10,000km travelled or within 1 year – whichever comes first. However, as previously mentioned, this is also highly dependent on the quality of engine oil being used, as some more durable and are less prone to breakdown than others.
You should also consult the owner's manual to verify the exact oil weight (viscosity) and specifications needed for your car to ensure compatibility. Numbers like 0W-20 or 10W-30 might sound confusing but do have a big impact on engine performance and health.
Types of engine oil
- Mineral Oil
Mineral oils are directly derived from refined crude petroleum oil. They are the cheapest because there's not much engineering going into them. The only refinement process that goes through it is the removal of natural contaminants and unwanted hydrocarbons.
For running-in freshly built engines, good mineral oil is important as it allows the various components to break in properly. But because they do not have additives, their molecular structures break down fast, so you need to change them frequently.
- Fully Synthetic
Fully Synthetic oils are chemically modified oils with additives and have fewer impurities. The additives are added to suit what an engine needs, such as good flow at low temperatures and stable viscosity at high temperatures.
There's no debate that fully synthetic oil is the best kind of oil to put in your engine, regardless of age or design. It usually has the most additives and is the most resistant to temperature and abuse, so it would be our oil grade of choice whether dealing with a 30-year-old classic car or a brand-new Honda HR-V.
- Semi-synthetic
Semi-synthetic oil is more expensive than mineral oil but cheaper than fully synthetic. The simple reason for this is that they are a mix of the two. Although they can provide the same protection features as fully synthetic oils, they are less potent than fully synthetic oils.
As a result, they are often used as an economical alternative to fully synthetic oils for people that do not need a maximum amount of performance and engine protection. They are commonly used in high-mileage engines, as engine deterioration has already taken its course in high-mileage cars.
Obviously, there is a lot more to nitty gritty, geeky, science-ey details of engine oils but those will at least get you over the line if you were wondering which one to pick up for your car and how they work to ensure smooth running.
Of course, our friends at Caltex have a broad range of high-quality engine oils and other lubricants to keep your car’s engine in top-notch mechanical condition.
Keyword: Quality oil is essential to the health of any engine - Car Basics with Caltex