More people are keeping their vehicles for long periods of time; finally, manufacturers have caught onto this fact. Now, they are producing synthetic oils that are designed to lubricate engines better. It’s called synthetic oil, and it’s a popular alternative to conventional mineral oil. But should you switch to synthetic oil in a higher mileage vehicle? Or should you use high mileage oil?
Let’s find out.
**Note** – A quick hello to anyone reading this, I’m Alastair and this is my site Synthetic oil.me. I started this site to help people with their oil questions, and hopefully what you’re about to read will help answer your questions. This page may include affiliate links to the likes of Amazon, which if you make a purchase I qualify to earn a (typically small) commission. Don’t worry as this won’t cost you anything, the likes of Amazon pay any commissions. Thank you in advance for your support as this helps bring you more (hopefully) helpful content.
What is Synthetic Oil?
Is synthetic oil any different from conventional engine oil? Yes. Synthetic oil is a special kind of lubricant for engines that have been artificially derived from petroleum molecules. Under a microscope, the molecules in synthetic oil are all the same size, while conventional oil is composed of molecules of various shapes and sizes.
If you get a fully synthetic oil, it is uniquely designed without petroleum and will have additives that prevent the breakdown of the oil. Meanwhile, synthetic blends contain both synthetic bases and conventional oil.
Benefits of Synthetic Oil
New and older cars can benefit from synthetic oil because it:
- Offers greater protection against engine wear and leaks.
- Keeps the engine cleaner. Full synthetic oils have fewer impurities than conventional oil and blends, so there is less sludge built up in the engine. Using the right kind of synthetic oil could improve engine function after one oil change.
- Protects the engine better in high temperatures.
- Flows better in cooler temperatures.
- Protects turbocharged engines better than conventional oil. Turbocharged engines (more revolutions per minute) operate at a higher temperature than larger engines. Using full synthetic oil will protect the engine better, because it has less viscosity and flows more smoothly.
The Myth of Synthetics
One argument that continues to circulate around the internet and beyond is that synthetics could damage an older vehicle. People thought that the rubber seals in an engine would break down when synthetic oil was used, causing issues that didn’t exist before. While this was blamed on the viscosity of synthetic oils, there was only a grain of truth in that.
The issue was that synthetic blends were not being formulated to prevent oil breakdown, sludge, and leaks. Now, fully synthetic oils have been created that completely turn the myth about on its head, like Mobil 1 Extended Performance High Mileage full synthetic.
If you are worried about leaks forming, aim for a full synthetic oil. Dealing with a lot of sludge? Shorter intervals between oil changes (about 3,000-5,000 miles) are better than waiting longer.
Synthetic Oil vs High Mileage Oil
So how do you choose between one synthetic oil and the next? The first method is looking at the make, model, and year of your car. If you own a newer car, the synthetic oil is perfectly fine. In fact, newer cars are designed to run on synthetic blends and benefit from them.
Older cars, or those with high mileage, should use high mileage oil. You can use synthetic oil on vehicles from 1990 to early 2000, but the vehicle needs to be in good running condition and will need the oil filter changed every time the oil is changed. Consider switching to high mileage synthetic oil as soon as your vehicle reaches 75,000 miles.
Is switching to synthetic oil for a higher mileage vehicle a good idea? Your mileage may vary. Usually, when a vehicle engine is maintained and kept in good running condition, you won’t have much to worry about. Synthetic oil could even sustain the engine for longer than average. If you are planning on switching to synthetic oil, it is best to discuss it with a professional mechanic who can inspect your car. They can let you know if it is right to switch or not.
If you own a Chevy Silverado or any other vehicle with a 5.3 liter Vortec V8 engine that is racking up the miles, check out our best high mileage oil review for these engines.