Can you mix 5W-20 and 5W-30?

I just changed my oil and realized I used 1 gallon (4 quarts) of 5W-30 and 2 quarts of 5W-20 by mistake.

When I was logging the oil change, I saw on the receipt that the two quarts were different.

Will this be a problem if am planning to drive 900 miles?

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Hi Alex, It’s generally not recommended to mix different viscosity grades like 5W-20 and 5W-30 motor oils. Mixing can alter the oil’s performance characteristics and potentially affect engine lubrication and efficiency. It’s best to use the oil viscosity recommended by the manufacturer for optimal engine performance and longevity.

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I assure you, using any combination of those oils will not pose any issues. I don’t understand why people get so worked up about oils. From my personal experience, as long as the oil is somewhat close to what’s recommended, you should be perfectly fine for regular use. Using either 5w-30 or 5w-20 oil won’t cause any harm to your engine, even if it’s a newer model.

Based on my research, it is generally not recommended to mix 5W-20 and 5W-30 motor oils in the same engine. These two oil viscosities have different thickness and flow properties, and using a blend can negatively impact the engine’s lubrication and performance. 5W-20 is a thinner, lower viscosity oil typically used in newer, more fuel-efficient engines, while 5W-30 is a bit thicker and better suited for older or higher mileage engines. Mixing the two could lead to increased oil consumption, reduced fuel economy, and potentially cause damage to engine components over time. The best practice is to use the specific oil viscosity recommended by the vehicle manufacturer, as indicated in the owner’s manual. Sticking to a single viscosity grade is the safest approach to ensure proper lubrication and protect your engine.

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Hello guys, ok it is actually not recommended for you to mix 5w-20 and 5w-30.