It's not uncommon for car owners to mix two brands of synthetic oil. In fact, many mechanics recommend it. The thinking is that by mixing the oils, you'll get the best of both worlds - the benefits of each oil.
However, there are a few things you should keep in mind if you're going to mix oils. First, make sure that the oils are compatible with each other. You can check this by looking at the back of the bottle or can - most manufacturers will have a list of compatible oils. If you're unsure, ask your mechanic or consult a professional.
Second, remember that when you mix oils, you're diluting each one. So, if you're using a high-quality oil and mixing it with a lower-quality oil, you're effectively lowering the quality of your overall oil mixture. This could shorten the life of your engine or cause other problems down the road.
Finally, be aware that mixing two different brands of synthetic oil will void most manufacturer warranties. So if something does go wrong with your engine while using a mixed oil blend, don't expect your warranty to cover it.
All things considered, it's generally safe to mix two brands of synthetic oil - as long as you do your research and use compatible products. Just be aware that by doing so, you could be compromising the quality of your motor oil and voiding any warranties on your vehicle.