The simple answer: Yes. There is no danger mixing
synthetic and conventional motor oil; however, conventional oil will
detract from the superior performance of synthetic oil and reduce its
benefits.
The detailed answer: With synthetic lubricants continuing to grow in popularity, the question of whether synthetics and conventional oils can be safely mixed often arises. I’m guilty of having mixed different types of motor oil with reckless abandon back in the day. A dash of synthetic blend to top-off my early 90s Buick Century one month and maybe a shot of cheap conventional oil the next. Though I’m sure performance suffered some, my engine never blew up as a result. So, yes, you can safely mix synthetic and conventional oil. But barring an emergency, it’s not a great idea.
Compatible components
All motor oil, whether synthetic or conventional, is a combination of
base oils and additives. Synthetic base oils are manufactured using a
process that removes the impurities inherent to conventional base oils.
Synthetics typically contain higher-quality additives, too. So, in the
end, conventional and synthetic oils are comprised of the same,
compatible components – it’s just that the components in synthetics are
much higher quality. While you can safely mix synthetic and conventional
oils, you’re doing nothing more than diluting the performance of the
synthetic oil.
You may not have a choice in some cases. If you’re traveling, for
example, and suddenly find your engine low on oil, cheap conventional
oil may be the only option at the gas station alongside the highway.
While it’s safe to top-off an engine that normally uses AMSOIL synthetic motor oil
with conventional oil, we recommend changing the oil at your earliest
convenience. In fact, AMSOIL does not support extended drain intervals
where oils have been mixed.
When you’re using the best oil available, why add anything to it?
If you’re looking for the most reliable synthetic oils or just need more information call Nick with Missouri Synthetics at 816-679-1599. Be sure to check out our
online shop for all your oil needs, including motor oil, fuel additives and filtration products.