Last Updated: 06.01.2022

Lower viscosity oil grades like 5w30 and 10w30 have done a great job of supporting efficiency as well as improving fuel economy.

Similar changes are also apparent for personal car engine lubrication where there is a move toward 5w30 and 10w30. The variety you settle for your vehicle depends on different factors like the total mileage, external environment, as well as driving conditions. You’ve probably been wondering, “what is the difference between 5w30 and 10w30?”

Let’s cover the major differences between these two oil viscosity grades and help you decide on the better option for your vehicle. 

What Is Engine Oil?

pouring oil into an engine

The main purpose of engine oil is to lubricate and cool off any moving components in your car’s engine. Engine oil contains the right balance of base oils and additives.

Base oil performance is divided into synthetic, mineral, or a combination of the two categories called synthetic blend. Additive performance, on the other hand, is defined by the quality of the additive and how much goes into the formulation. Selecting the right combination of additive and base oil is the ultimate challenge.

The base oil is the main carrier for engine oil, which accounts for up to 90% of the formulation. The base oil is very important in determining viscosity.

What Is Viscosity When Selecting Engine Oil?

One of the most important things to consider when selecting engine oil is viscosity. It is a measure of the resistance of engine oil to flow or motion.

The resistance keeps oil from being squeezed out from between engine surfaces when they are moving under pressure or load. It determines how the oil flows or moves over a wide temperature range. There are two types of viscosities: single-grade and multi-grade.

Single-grade viscosity oils don’t have a polymer additive. Single-grade viscosities include 5W, 0W, 15W, 10W, 25W, 20W, 60, 50, 40, 30, and 20.

Multi-grade viscosity oils, on the other hand, contain polymers (viscosity index improvers). They are usually formulated to flow more easily at startup when the engine is cold. Some popular examples of multi-grade viscosity oils are 5w30 and 10w30. 

The 10w means that the oil flows like a lighter oil at startup and the W stands for winter. The moment the engine has reached operating temperature, a 10w30 oil flows like a heavier SAE 30 oil.

What Is 5W30?

This is a multi-grade viscosity oil that offers the best of both worlds in terms of performance. You get good startup and low-temperature protection. The W as we mentioned earlier stands for winter. So, at those low temperatures, the oil will flow at a kinetic viscosity of 5. And at high temperatures, the oil flows at a viscosity of 30.

Top 3 5W30 Motor Oils

Here are our top 3 5w30 motor oil recommendations:

1. Mobil 1 Extended Performance 5w30 Motor Oil

Mobil 1 Extended Performance 5w30 Motor Oil

Mobile 1 is a proven, excellent, premium quality 5w30 oil for the daily driver. With this formulation, you can effectively improve your fuel economy.

It is a thin oil that ensures your oil pump doesn’t work too hard. This oil will provide up to 20,000 miles before the next oil change. It can meet as well as exceed your expectations. Mobile 1 helps improve engine life by preventing sludge and deposit buildup.

You should expect the best wear protection and lubrication under many operating conditions. We think this oil is great for modern gasoline vehicles, including vans, cars, SUVs, as well as trucks. 

2. Castrol GTX High Mileage 5W30 Motor Oil

Castrol GTX High Mileage 5W30 Motor Oil

Your vehicle may be aging but using the right motor oil can help extend its life. We think this synthetic blend is very good at resisting thermal breakdown better than most competing oils on the market.

It does a great job of stopping damaging deposits from developing under high temperatures. This high mileage oil also contains steel conditioners, which is great because it helps keep your engine seals in top-notch condition. The other thing we like about this formula is that it has patented phosphorus replacement technology, which helps improve wear protection.

It is recommended for engines that go over 75,000 miles.

3. Valvoline High Mileage 5W30 Motor Oil

Valvoline High Mileage 5W30 Motor Oil

You can protect the investment of your vehicle and help maximize its life by using this high-quality motor oil from Valvoline.

We like the fact that this thin synthetic blend is uniquely formulated to fight four main signs of engine wear, such as loss of fuel economy, reduced power, increased oil consumption, and oil leaks. This formula lubricates as well as cleans your engine to reduce wear and lower engine temperature.

Another thing that we like about this 5w30 is the special anti-wear additives that are very good at reducing abrasion and preventing a reduction in your car’s engine power.

What Is 10W30?

This is the second most popular multi-grade viscosity oil on the market. The W refers to winter. With this type, the oil has a viscosity of 10 at low temperatures in the winter and a viscosity of 30 when the temperatures are high. 

Top 3 10W30 Motor Oils

Here are our top three 10w30 motor oil recommendations:

1. Pennzoil Conventional 10W30 Motor Oil

Pennzoil Conventional 10W30 Motor Oil

When you are in the market for a high-performing 10w30 oil, we think Pennzoil Conventional is one of the best options for your vehicle.

This formula offers unmatched cleansing as well as protection. One of the things that we like about this motor oil is the active cleansing agents that it comes with. They can keep your engine clean and also contribute towards removing deposits.

This product also contains seal conditioners, which penetrate the seals and help to swell and condition them to stop leaks.

2. Royal Purple 10W30 High-Performance Motor Oil

Royal Purple 10W30 High-Performance Motor Oil

Have you been looking for a high-performing 10w30 motor oil that features premium base oils and proprietary additive technology? This oil from Royal Purple might be what’s suited for your needs.

One of the main features of this motor oil is its high-film strength that helps lower emissions, improves fuel economy, and reduces maintenance. Within any combustion engine, many parts must be protected by a thin film of motor oil. We think this great formula from Royal Purple will help reduce friction as well as provide good sealing.

We also like the fact that this formula contains advanced additive chemistry that does a great job of reducing low-speed pre-ignition.

3. Shell Rotella T5 10W30 Diesel Engine Oil

Shell Rotella T5 10W30 Diesel Engine Oil

Do you want to protect your vehicle in challenging environments? You can give your vehicle the best lubrication and wear protection with this great 10w30 motor oil from Shell.

We really like the synthetic blend formulation, which offers the protection you have always been looking for. You don’t have to worry about low-temperature flow, oil breakdown, deposits, or wear. We find the advanced additive technology to be quite reliable as far as controlling deposits is concerned. You can expect an increased fuel economy of up to 2%.

We also like the fact that it has superior cold cranking properties as well as low-temperature performance.

Main Differences Between 5W30 and 10W30

These are the main points of comparison between 5w30 and 10w30.

Temperature Range

This is a significant difference between 5w30 and 10w30. The 5w30 motor oil is suitable for a temperature range that is greater than 10w30.

The 5w30 will remain a viscous fluid from -35°C to 35°C, whereas the 10w30 remains a viscous fluid from -16°C to 30°C. According to these figures, 5w30 seems to be the better option for colder regions. On the other hand, 10w30 is considered a superior option for summer.

Corresponding Viscosity

The next distinct difference between 5w30 and 10w30is their corresponding viscosity. According to the figures, the 10w30 viscosity is higher than that of the 5w30.

That’s why the 10w30 offers better performance in hotter conditions, while the 5w30 provides superior performance in colder conditions. The lower viscosity index of the 5w30 means that it can effectively penetrate the hard-to-reach spots of your vehicle’s engine. Although, it thins out rather quickly when temperatures are high.

Vehicle Type

These two motor oil viscosity grades are recommended for different categories of vehicles. The low viscosity index and thinner formulation of the 5w30 make it a better option for light-duty diesel as well as petrol engines. This includes small to medium-sized automobiles.

In contrast, the higher viscosity index and thicker formulation of the 10w30 make it a better option for heavy-duty hauling engines. It is the motor oil you would want in your bus or truck. It is also a great choice for older engines. 

Difference Between 5w30 and 10w30 – Verdict

They are both multi-grade motor oils, which have proven to be quite reliable as far as improving fuel economy is concerned.

The 5w30 offers better cold-weather starting as opposed to the 10w30. The 10w30, on the other hand, thins out less quickly at higher temperatures maintaining better performance in summer. The thinner formulation of the 5w30 offers better lubrication of hard-to-reach parts, while the heavier formulation of the 10w30 offers moderate lubrication of those tight spots in your engine.

Based on their specific features and performance on the road, 5w30 comes highly recommended for light-duty diesel and petrol engines, while 10w30 is highly considered a better choice for heavy-duty hauling engines.