Can You Mix 5w20 and 5w30 Engine Oil? Here’s All You Need to Know

It’s important to understand that 5w20 and 5w30 are both multi-grade oils, which means they have a number of viscosity grades within their formulation.

For example, the base oil may be 10 weight (10W), but it can also be 20 weight (20W) or 30 weight (30W). So, when you see a 5w20 or 5w30 label on an oil bottle, that means it’s a multi-grade oil with 2 different viscosity grades within its mixture.

Also, the purpose of the two different types of motor oil is to help your engine run smoothly in a range of temperatures. The number after the w stands for winter. This means that it’s meant for cold weather.

The lower number is good in most situations, but if you’re driving in freezing temperatures or at high altitudes (like mountains), then using a 5w20 or even a 5w30 will give your engine more protection from extreme weather conditions.

So, can you mix 5w20 and 5w30?

Yes, you can mix 5w20 and 5w30. The best thing about mixing these two brands of motor oils is that they are both made by reputable manufacturers who follow all industry standards when making their products such as using high-quality base stocks, additives, and so on.

In this post, we’ll be answering some of the most asked questions about mixing 5w20 and 5w30 engine oil types and every other thing you need to know.

can you mix 5w20 and 5w30

Reasons Why You Can Mix 5w20 and 5w30 Engine Oil

There are two main reasons you can mix oils. First, both are designed to work in a wide range of temperatures, and second, they have the same viscosity (5W) though their viscosity index is different.

You may have heard that 5W30 is better than 5W20, or vice versa. But this isn’t true. Both types of oil have the same viscosity (5W) even though their viscosity indices are different.

The viscosity index is a measurement of how much the oil thickens at low temperatures. Light, thin oils like those used in summer weather need to thicken more than heavier, warmer-weather-type oils do to remain liquid at colder temperatures.

What Happens When You Mix 5w20 and 5w30?

When you mix both the 5W20 and 5W30 oils together, there is nothing significant that will happen. The vehicle’s engine will run smoothly. In fact, it will still be able to cope with all the driving conditions that come its way.

You might have heard people talking about the difference between these two types of motor oils but they are not that different at all. They only differ in their viscosity rating which makes them thicker than other types of motor oil. We’ll learn more about the differences as we proceed.

What Are the Main Differences Between 5w30 and 5w20?

1. Velocity Level

The main difference between the two is that 5W20 oil operates at a lower temperature when compared with 5W30. This means that when your car is idle or traveling in stop-and-go traffic, it can operate much more effectively with 5W20 oil than with 5W30.

However, at higher temperatures (which are common during highway driving), both oils become increasingly viscous, and their ability to function decreases.

Therefore, while you may experience better cold weather performance because of the reduced viscosity of 5W20 over its counterpart, this advantage will be lost once things heat up and both oils become too thick to flow properly through your engine’s moving parts.

You should also know that 5W20 oil operates better at a lower temperature when compared with 5W30 oil. In fact, the safe operating temp range is almost the same, but 5W30 can be used up to 230 degrees Fahrenheit without suffering any adverse effects (like overheating).

5W20 will start to break down at just 195 degrees Fahrenheit. This means that if you have an older car or one with a less efficient cooling system, it’s best to stick with 5W30.

The extra viscosity will help keep your engine from getting too hot if you’re stuck in traffic on the way home from work in the summer heat.

Read: Can You Mix 5w 30 and 10w 30?

2. Viscosity Index

The viscosity index (VI) of a lubricant is a measure of its resistance to thinning as the temperature increases. The VI value is an indication of how much the oil will thin under load.

Generally speaking, this is good because it means that your engine will be protected at high temperatures. However, if your car calls for 5W20 and you use 5W30 instead in order to get more miles per quart, you may find yourself with some serious engine problems down the road.

The reason for this comes down to viscosity. 5W20 has a lower viscosity than 5W30 because it has less base stock in its blend. The lighter blend makes it easier for engines with tighter tolerances that might otherwise overheat when using heavier oils such as 30 weight or heavier.

When you switch from 20 weight all the way up through 50 weight grades on an older car without changing any other components such as coolant flush intervals, there could be issues with overheating.

The Pros of 5w20 and 5w30

The advantage of using multi-grade oils is that they allow you to use them in all types of weather conditions with less risk of experiencing engine damage or failure.

This is because the fluid has been formulated so that it has a high enough viscosity to provide adequate protection in colder temperatures while still being thin enough for warmer temperatures where it could potentially cause overheating problems if the viscosity was too thick.

When/Where To Use 5w20 or 5w30

If you live in a hot climate area, 5w20 or 5w30 is the best option for your engine. It’s lighter than other viscous oils and has less internal resistance. This allows it to flow freely and dissipate heat more quickly. This also means that you won’t be using as much oil over time, so it will last longer than other oil types.

If you have an older car or one with high mileage on the clock, 5w20 or 5w30 is the way to go because they can help extend engine life by keeping friction down and helping prevent wear inside components like pistons and bearings.

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5w20 and 5w30 are both multi-grade oils. This means that they can be used in engines running on low-viscosity (thin) oil or high-viscosity (thick) oil. The difference between the two is their weight: 5w20 is lighter than 5w30.

You can mix 5W20 and 5W30 oil, but you should only do it if your car’s manual doesn’t specify which grade to use. If you don’t have the manual or if it does specify a particular grade of oil, stick to following the manufacturer’s recommendations.

These oils have different viscosity indexes but they have the same viscosity of 5W. The higher the viscosity index, the more viscous your oil will be. This means that it will flow less easily and takes longer to heat up or cool down.

The lower the viscosity index, the thinner your oil will be with better flow characteristics at high temperatures (hotter) like when driving in traffic during summer months in hot cities like Los Angeles where temperatures can reach 100 degrees Fahrenheit.

They also lubricate well which means less friction so that parts won’t wear off quickly while driving around town doing errands or taking trips across country roads.