Can different brands of engine oil be mixed?
2 Answers
No, different brands of engine oil use different additives. Here is a detailed introduction of relevant information: Relevant part: Engine oil is the lubricating oil for engine operation, which plays the roles of lubrication, cleaning, cooling, sealing, and reducing friction. The oil filter is the component that filters the engine oil. During the engine working process, metal shavings generated by friction of various components, impurities in the inhaled air, and oxides of engine oil are all objects filtered by the oil filter. Effects of mixing: Mixing different grades of engine oil will cause turbidity, mixing different brands of engine oil will also cause abnormal smoke in the exhaust, and mixing different engine oils will produce sludge, causing the engine to overheat and changing its anti-wear performance.
I've been repairing cars for over ten years and often see car owners asking if they can mix different brands of engine oil. Honestly, my experience suggests it's best not to do so. Engine oil formulations are complex, and additives from different brands may conflict. Mixing them can lead to sediment clogging the oil passages and accelerating engine wear. Last time, a client mixed two types of full synthetic oil, and the car immediately became noisier—turns out, the additives reacted and formed sludge. In emergencies, if you must mix oils, ensure the viscosity and base oil types are similar, such as both meeting API SN standards, but change the oil as soon as possible afterward. Mixing oils carries significant risks; protecting the engine is more important than saving money. Using the same brand during regular maintenance is the safest approach, preventing costly repairs later. Remember, engine oil is the lifeblood of your car—don't compromise long-term health for minor convenience.
