Conventional motor oil is a refined crude oil product. Synthetic motor oil is a man-made product produced from a variety of highly engineered ingredients. Full synthetic oil offers the best lubrication, stability, viscosity retention, and sludge prevention. These features of synthetic oil translate to better gas mileage, smoother performance, and better protection against engine wear compared to conventional oil. Plus, vehicles that use synthetic oil usually have longer oil change intervals. That’s more convenient for you and better for the environment.
The benefits of synthetic oil outweigh the extra cost. AAA’s 2017 study1 found that one synthetic oil change every 7,500 miles costs just $5 more per month than conventional oil, while outperforming conventional oil by 47%. Since better oil performance contributes to long-term engine health, synthetic oil is a great investment in the longevity of your vehicle.
When in doubt, a full synthetic oil change every 7,500 miles (or sooner, if your oil reminder activates) is a great rule of thumb. But check your vehicle’s manual -- manufacturers today recommend oil change intervals ranging from 5,000 miles to a whopping 15,000 miles, depending on the vehicle. Today’s longer oil change intervals assume you’re using a type of oil that meets your vehicle’s specifications -- a synthetic blend or better, in most cases. (Don’t worry - Midas never uses engine oils below your vehicle specs.)
It’s a myth that synthetic oil causes leaks. But the myth persists because it’s based on an outdated fact. Back in the 1970s, synthetic oils did sometimes degrade engine seals made of certain materials. Today, synthetic oils help protect your seals.
Synthetic oil does not cause leaks, but you may notice an existing leak after your first synthetic oil change. That’s because synthetic oil can clear away conventional oil build-up that was plugging an existing leak. So synthetic oil doesn’t cause the leak -- it diagnoses it! It may be time for High Mileage Oil. It’s designed to fill in those small gaps and prolong the life of your engine.
In a study released on June 7, 2017, AAA compared multiple brands of conventional and synthetic engine oil in eight industry-standard tests: shear stability, deposit formation, volatility, cold-temperature pumpability, oxidation resistance, and oxidation-induced rheological changes. Learn more about the AAA oil study.↩