When it comes to engine oil or motor oil, you may think they’re all the same. You bring your vehicle in for an oil change and never wonder what kind of oils are available. There are actually four main types, each tailored for different kinds of engines and with different pros and cons. Next time you bring your car or truck in for an oil change, ask your mechanic what’s going into your engine.
Regular or Conventional Motor Oil
Most vehicles on the market today are filled with conventional engine oil. After all, this is the most popular kind of oil on the market and has existed for over a century. This makes it a tried-and-true product that many mechanics have been taught to use.
The nice thing about regular motor oil is that it’s usually cheaper than synthetic oil and has lubricated and protected standard engines for a very long time. Most people consider cost when they bring their car, truck, or SUV in for maintenance, so this is the oil they prefer to buy.
The downside to this oil is that while you save some money initially, it needs to be changed more often than other kinds of oil. The general recommendation is that every 3,000 miles or six months, conventional engine oil should be changed. This can change depending on various factors, including the type and age of the car, how much it has been driven, how you drive it.
Synthetic Engine Oil
There’s been a larger push lately to increase the use of synthetic motor oil. Some would argue that technology has marched on, and synthetic oil is a far superior product to conventional engine oil. BMW actually recommends it for use in its engines.
Why? The upside to this oil is that it contains additives that resist heat better than regular motor oil does. Some engines, such as those in BMWs, are high-performance and tend to run hotter than others. This is because synthetic oils have more stable molecules, reducing oil burn-off in the heat.
Synthetic oil also holds up to temperature changes and extreme climates better. If the temperatures often reach below zero Fahrenheit where you live, synthetic oil is a much better choice for you.
Of course, synthetic oil is a bit more expensive than conventional oil. However, you only have to change every 7,500 to 15,000 miles, depending on the brand and your manufacturer’s recommendations.
Synthetic Blend or Semi-Synthetic Oil
Semi-synthetic motor oil is a blend of conventional and synthetic oils. This helps bring the cost down while giving some of the benefits of fully synthetic motor oil. Its popularity is dwindling as fully synthetic oil continues to grow in prominence.
This is for two reasons: reduced quality and changing manufacturer’s requirements.
Obviously, a blend of synthetic and regular engine oils will give you some benefits of synthetic oil, but how much benefit comes down to how much synthetic oil is in a brand’s particular blend. This means that the quality of different products can vary widely — too widely for some people.
This quality discrepancy means that there’s no uniform blend of semi-synthetic engine oil, so manufacturers aren’t sure what to recommend in regard to them. It has become more difficult for synthetic blends to meet manufacturers’ requirements lately.
High-Mileage Engine Oil
High-mileage engine oil is a kind of conventional motor oil that’s specifically designed for engines that have more than 75,000 miles on them. This kind of oil uses conventional engine oil as a base and adds ingredients to stop help stop leaks before they begin. This is because older engines are prone to developing oil leaks, which is an effective way to critically damage your engine.
Just as with conventional oil, the high-mileage version needs to be changed every 3,000 miles.
High-mileage motor oil flows more slowly than other oils and is much thicker than other oils, including synthetic oil. If your engine springs a leak, this thicker, lower-flowing oil won’t seep out as quickly, keeping your old engine from overheating and becoming damaged as fast. It’s best to use high-mileage oil if you have an old vehicle and have already noticed signs of leaking.
Your Mechanic Can Help
Your mechanic or auto repair shop should be willing to help you make a decision that’s best for your vehicle and situation. Ultimately, you can have a say in what kind of oil goes into your car, and your mechanic should be able to explain the differences between them and make a recommendation for your engine.