I have been a mechanic for many years. This question has came up more times than any other question. Here is the technical answer to it. First off every motor oil sold in the united states has to meet API/SM standards. If the oil you purchase does NOT have this identified symbol saying it meets API/SM standard, Then DO NOT use it. If the symbol is there and they are both the same weight, and same kind of oil. (conventional or synthetic) Then any and car manufactures HAVE to allow the oil to be used in there vehicles. With that being said, Feel free to mix different brands of oil. I promise you that it will not hurt your vehicle. API/SM is the standard that ALL oil and vehicle companies use as a guide for proper viscosity as well as the degree of quality used in manufacturing. If any one tells you different then I would have you look it up with the department of weights and measure. As well as the national lubrication foundation. I have done extensive research. I hope this has helped you, and good luck By Doke ....
