Full Synthetic vs. Synthetic Blend Oil

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Every car with an internal combustion (gas) engine needs oil to keep all its moving parts cool and lubricated. Conventional oil is typically the standard, and many quick-change spots and dealerships will automatically use it if not specified otherwise. High-performance engines and powertrains with high miles will typically be better off using full synthetic oil. There are also synthetic blends that use a mixture of conventional oils and full synthetics. Here, we’ll point out the differences between the two and which you should use.

Full synthetic oil

Full synthetic oils use a synthetic base refined to be contaminant-free and mixed with additives to enhance their performance. Most brands formulate full synthetic oil to reduce friction on the engine’s moving parts and keep them clean, but each company determines its specific composition. It also lasts longer than conventional oil, increasing the oil change intervals. Most high-performance engines that use turbochargers or superchargers often require full synthetic oils. Full synthetic oil also performs better in cold weather. Synthetic oil tends to be more expensive and can cost about two to three times more than conventional oil.

Synthetic oil blends

Synthetic blend oils are exactly what they sound like. They use a mixture of synthetic oil and conventional oil, along with some additives. This way, the oil provides increased performance at a slightly lower cost. The ratio of synthetic to conventional varies by brand, but most of the time, the majority is traditional oil.

What’s the difference?  

Full synthetic oil is completely lab-made and has higher purity and performance. Synthetic blends use a base of conventional oil mixed with synthetic oil to balance performance and cost. Though it's more expensive, full synthetic oil lasts longer, provides better protection and lubrication for the engine, and helps it perform in extreme temperatures. Some engines require total synthetic fuels, like high-performance engines in sports cars. Compared to straight conventional oils, synthetic blends have some of the improved protection and lubrication characteristics of full synthetic oils, and they last a bit longer than going with any standard oil. Many small, fuel-efficient cars with turbochargers must use synthetic blend oil as the minimum recommended grade.

What oil should I use?

Full synthetic oil may last longer, but it is more expensive and unnecessary for most vehicles. Synthetic blends combine conventional and synthetic oil and offer some of the performance benefits of full synthetics at a lower price. Ultimately, it comes down to what kind of car you drive and how much you want to pay.