Can engine oils of different brands be mixed together?
2 Answers
Engine oils of different brands should not be mixed together. Different brands and grades of engine oil are formulated with various additives based on the working characteristics and environmental requirements of different engines, resulting in differences in viscosity, anti-wear properties, corrosion resistance, anti-knock performance, and volatility. The functions of engine oil include: 1. Separating the surfaces of relatively sliding parts such as pistons and cylinders, main shafts and bearing bushes to reduce component wear; 2. Carrying heat back to the oil tank and then dissipating it into the air to help the radiator cool the engine; 3. Forming a seal between the piston rings and pistons to reduce gas leakage and prevent external contaminants from entering; 4. Adsorbing onto component surfaces to prevent contact with water, air, acidic substances, and harmful gases; 5. Cushioning impact loads on pistons, piston chips, connecting rods, and crankshaft bearings.
As a veteran driver with over a decade of experience, I don't think it's a good idea to mix different brands of engine oil. The engine requires a stable lubrication environment, and each oil brand has its unique formula. Additives such as detergents or anti-wear agents may not be compatible. Mixing them could lead to chemical reactions that form sludge or deposits, accelerating engine wear or even causing overheating issues. In emergencies, like when you're low on oil and have to top up, mixing a small amount temporarily is acceptable, but don't delay—replace it entirely as soon as possible. My advice is to stick with one brand of oil for peace of mind and to extend engine life. Remember to check the oil level regularly, and if it turns black or shows signs of burning, address it promptly. These small habits can save you from major headaches.
