Is Fully Synthetic Oil Mandatory for Turbocharged Engines?
2 Answers
Turbocharged engines are not required to use fully synthetic oil, but they generally do because fully synthetic oil is thinner, which benefits the turbocharger's lifespan, allowing it to last tens of thousands of kilometers longer. Typically, a turbocharger needs replacement around 100,000 kilometers, but using fully synthetic oil can extend its service life. Turbocharged engines have specific requirements for oil: it must have excellent wear resistance, high-temperature tolerance, strong oil film strength, and high shear resistance. Fully synthetic or semi-synthetic oils are the best choices to meet these requirements. Fully synthetic oil is entirely chemically synthesized and fulfills the demands of turbocharged engines. It excels in fluidity, lubrication, cooling, oxidation resistance, and cleaning capabilities. Initially, fully synthetic oil was widely used in aircraft engines and racing engines due to its superior performance in harsh environments, providing excellent engine protection. Therefore, it is advisable to use fully synthetic oil for turbocharged engines. The working environment of turbocharged engines is indeed unique, so it is recommended to use high-quality synthetic oil during maintenance. The biggest issue with turbochargers is the extremely high temperatures during operation, making rapid cooling a primary concern. Ensuring proper lubrication is crucial for normal operation, and turbocharged engines run hotter than naturally aspirated engines. Thus, turbocharged engines require oil with excellent cooling properties and high fluidity. If a turbocharged car uses fully synthetic oil, its maintenance interval is longer compared to mineral or semi-synthetic oils, typically allowing oil changes every 10,000 kilometers. Therefore, the benefits of using fully synthetic oil are substantial. Semi-synthetic oil has poorer fluidity and lower viscosity, making the engine prone to overheating and potential failures during operation. Hence, turbocharged engines are best served by fully synthetic oil, which offers better fluidity, lower resistance, and superior engine protection compared to semi-synthetic oil.
After driving turbocharged cars for so many years, I've noticed the engine operates at significantly higher temperatures, causing conventional oil to degrade and fail more easily. Full synthetic oil maintains much better stability under high heat, effectively reducing friction and preventing turbocharger bearing seizure. While manufacturers may not mandate its use, I insist on full synthetic for long-term engine health and to avoid costly repairs—especially during long-distance highway driving. It not only improves fuel efficiency but also extends oil change intervals to 10,000 km versus mineral oil's 5,000 km, saving considerable hassle. Bottom line: Don't skimp on this small investment for your car's longevity.
