Yes, synthetic oils for passenger car and light truck use are fully compatible with petroleum oil and other synthetic lubricants. But, even though they are compatible it is best not to mix different brands of oil. Each brand of oil has a specific chemistry and additive package and two different oils mixed together may result in optimal performance as they were engineered to if the chemistries of the oil becomes offset by mixing with another brand of oil.

AMSOIL synthetic motor oils are fully compatible with all petroleum motor oils, and there is no danger in mixing the two. Mixing AMSOIL and petroleum oil, however, is not a recommended as a general practice. Performance and long drain intervals will be sacrificed and the oil should be promptly changed, at maximum, within the next 3,000 miles. AMSOIL Synthetic Motor Oil can be used during break-in trouble free.

Yes, AMSOIL Motor Oils are compatible with all other synthetic or petroleum motor oils. However, the mixing of AMSOIL with other oils will shorten the effective life of the AMSOIL lubricant. Top

Yes. Royal Purple lubricants are fully compatible with all currently available petroleum, petroleum/synthetic blends, or full synthetic based oils. The Synerlec technology provides the best protection and performance increases available, however, it is very expensive. We have blended our street oils to exceed the performance characteristics of any other blended or "Full" synthetic.

AMSOIL Synthetic Motor Oils are high performance, extended life oils manufactured from premium synthetic base stocks and special purpose additives. These "designer oils" (so nicknamed because their molecules can be structured to do a specific job) provide significant improved overall performance benefits over conventional petroleum oils. Top

Yes, it is compatible with any type of synthetic oil that is designed for vehicle engines or transmissions. Centurion / Opti-Lube has almost no effect on viscosity, it flows at -35? and can be used in light engine oils to heavy gear oil. No, it can be added any time. Centurion oil fortifier replenishes motor oil additives that deplete over time, including oxidation inhibitors, acid neutralizers and anti-wear additives. Adding at an oil change is just the most cost effective time.

A Yes. AMSOIL Motor Oils are compatible with all other synthetic or petroleum motor oils. back to top

AMSOIL Synthetic Blend Motor Oils are a blend of synthetic fluids and petroleum oils. They are combined to form an all season motor oil that demonstrates many of the performance features of synthetic lubricants.

Absolutely not. Both petroleum motor oils and synthetic motor oils have additives blended in the oil to control seal swell, shrinkage and other engineering parameters.

It's all in the formulation. Because AMSOIL is made with synthetic basestocks, it resists thermal and oxidative breakdown, which suits it for extended drain use. AMSOIL pairs top-quality long-life synthetic basestocks with top-quality long-life additives. The fact is, other oil companies don't use the quality additives AMSOIL uses because it simply doesn't pay to pair long-life additives with short-lived conventional basestocks.

Synthetic base fluids are manufactured over a number of complex chemical stages and are thus inherently more expensive than base oils extracted from petroleum.

Mobil 1 is fully compatible with conventional motor oils, semi-synthetic motor oils and other synthetic motor oils, should it be necessary to mix them. However, it is important to note that the superior performance of Mobil 1 will be reduced by diluting it in any way.

Yes, MT-10 is compatible with the major brand-name synthetic oils found in your local auto parts and discount stores. However, should you go outside the realm of these everyday synthetic oils, please consult with our Technical Dept. for further information. There are so many brands in the marketplace that we can't possibly list all those that are compatible with MT-10 here.

All motor oils are made up of base oils and additives. In general, fully synthetic motor oils contain non-conventional, high-performance fluids. Semi-synthetic oils (also called "blends") usually use a small percentage of non-conventional, high-performance fluids in combination with conventional base oil.