Can the same brand of engine oil be mixed?
2 Answers
Engine oil of the same brand can be mixed. The method for adding engine oil is as follows: 1. Pull out the oil dipstick, wipe it clean, and measure again to see how much oil is missing; 2. Open the oil cap to add oil, cover the cap and start the engine for a few minutes. After the oil has circulated in the engine for a while, check the oil dipstick again. If the liquid level drops, continue adding. The functions of engine oil include: lubrication, auxiliary cooling, cleaning, sealing and leak prevention, rust and corrosion prevention, shock absorption, and wear resistance. The method for changing engine oil is as follows: 1. Lift the car, remove the protective plate, and place a container of about 10 liters under the oil drain plug; 2. Unscrew the oil drain plug, use an air gun to blow for two minutes at the oil filler port, tighten the oil drain plug after draining, and wipe it with a tissue to check for leaks; 3. Reinstall the protective plate and lower the car, then use a funnel to align with the oil filler port to add engine oil.
As a seasoned car owner with years of driving experience, I remember being curious about this issue when I first bought my car. I tried mixing different viscosity grades of the same brand's engine oil a few times, such as blending 5W-30 with 10W-40. Initially, there wasn't much noticeable difference, but later the engine noise increased slightly. A repair shop inspection revealed uneven lubrication had accelerated component wear. The additive packages in engine oils vary significantly—even within the same brand, different product formulations may change, and mixing can compromise oil film stability. The key issue is that viscosity grades differ; blended oil's flow properties deteriorate, causing more cooling problems during summer or high-speed driving. My experience taught me: in emergencies, small amounts of the same product line can be mixed temporarily, but never haphazardly combine oils—long-term damage isn't worth it. Always opt for a complete oil change when possible. Regular maintenance checks on oil quality have saved me considerable repair costs over time.
