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A Basic Guide to Engine Oils

While most of us prefer to leave oil changes and oil filter changes to the professionals, not to mention fixing any problems involving engine oil leaks, it’s still useful to know about the different types of oils that are so important for protecting our car engines and keeping them running smoothly on a daily basis.

There are three sorts of engine oil: mineral, semi-synthetic and fully synthetic. Classic cars tend to be suited to mineral oil, while modern ones are more likely to use semi-synthetic oil or synthetic oil. Without going into too much detail, semi-synthetic and synthetic are designed for higher complexity engines and unfavourable conditions. Although it’s possible to switch between oils in certain cases, it’s never advisable to mix them.

What is Mineral Oil?

Mineral oil is natural oil taken from the ground. It tends to be cheaper than the other two types of engine oil, but also requires changing more frequently.

What is Semi-Synthetic Oil?

Semi-synthetic oil is a mixture of mineral oil and artificial additives. It combines the lower price factor of mineral oil with some of the benefits of fully synthetic oil (as far as engine protection, smooth running, longevity, etc.)

What is Fully Synthetic Oil?

Fully synthetic oil is entirely artificial. It tends to be the most expensive of the three sorts of engine oil. However, it has been engineered to safeguard your car engine, get the best performance from it and outlast other oils. Needless to say, you especially don’t want an engine oil leak when using an expensive fully synthetic oil.

What is Viscosity?

Stated very simply, viscosity is the thickness of a liquid. Obviously, this property affects how quickly and easily said liquid will flow. Vehicles will come with a recommended viscosity of oil (check the owner’s manual).

You’ll notice containers of engine oil display viscosity ratings such as “5W30”. The first number is how well the oil flows when the engine is cold. The second number is how well it flows when the engine is operating normally. The smaller the value, the better the flow. Low-viscosity oils protect the engine in the cold, while high-viscosity protect it in the heat.

Signs You Need an Oil Change and/or Oil Filter Change

  • The car’s indicators are telling you it’s time!
  • Knocking sounds from the engine
  • Smoky exhaust and oil smells (the later possibly inside the vehicle)
  • Other issues like vibrations while idling or gear changes not feeling normal
  • Reduced fuel economy
  • The oil itself looks dark and dirty.

For Engine Oil Leaks and Any Other Auto Repairs…

Mainstreme Automotive can help. Based in Dayboro, in the Moreton Bay region of Qld, we are a family business that’s been operating since 2001, earning numerous five-star reviews from our customers. As well as offering 24-hour towing (two trucks), we can service/repair most types of vehicles and are committed to providing the best possible work at a competitive price. For enquiries, email or , call (07) 3425 1503 or use the online enquiry form located here.

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