Did it sound slightly similar to hearing 10w30 and 5w40 to you?
You’re not alone. Primarily, most users are confused and think about what oil to choose for their car.
But, there is a silent battle between 10w30 and 5w40 in terms of viscosity, formation, heat resistance, protection capability, and
fuel economy.
Going deep down can help you to discover all of these differences. Otherwise, you find them similar in white eyes.
But, as the engine has to incorporate with the oil, that can understand the subtle differences.
So there is no way to choose the right one between them as it’ll help to keep your engine healthy and explore the satisfying driving on city, muddy, bumpy, or rocky roads.
Here, we walk you through the quick overview and the in-depth comparison between 10w30 vs 5w40. Trust us and invest two minutes going through this article to clarify your confusion.
Comparison Table Between 10w30 vs 5w40
Nothing but, a comparison table can provide you with the core differences in a bird eye view. This is why we keep this table to help you get the information in a nutshell.
| Features | 10w30 | 5w40 |
| Types | Available in conventional or mineral, synthetic, and semi-synthetic | Full Synthetic |
| Used for | Petrol and Diesel engines | Gasoline and Diesel engine |
| Viscosity Index | 146 | 176 |
| Temperature range | -13°f to +86°f | -13°f to +104°f |
| High-temperature Resistance | Thicker so higher heat resistance | Thinner, so lower heat resistance |
| Fuel economy | Good | Excellent |
| Compatible vehicles | SUVs, ATVs, Truck, and four-stroke engines | Passenger vehicles, automobiles, and light-duty trucks |
What Do 10w30 And 5w40 Mean In Engine Oil?
Let’s clarify the meaning of 10w30 and 5w40 engine oil.
Both oils are used as engine oil to lube its moving parts for smooth rotation so that they won’t be fragile due to metallic frictional engagement.
Here, in both cases, ‘W’ indicates winter or cold weather. The first number shows you the cold weather resistance level, and the second number shows the hot weather resistance level.
Another indication of the digit is the oil’s thickness and flowing rate. That means the higher number of oil is thick and the lower number of oil is thin.
So, the 10w30 oil takes more time to flow in cold and less time in hot weather. Because its first digit is higher and the second digit is lower.
On the other hand, the 5w40 takes less time in cold weather and more time in hot weather. The reasoning is the same: the lower first and higher second digit.
Hopefully, in short, you have got the basic concept about the oil.
A Quick Overview Of 10w30
The 10w30 oil is mostly persuasive for modern and older petrol and diesel-powered SUVs, ATVs, and Truck engines. It can resist low temperatures up to -13°f or -25°c in winter or when the engine is cold. In hotter weather, or when the engine runs hot for longer hours, its heat-resistant capacity will be upgraded to 86°f or 30°c.
That means you can pour this oil into your car’s engine to get healthy functioning at both high and low temp because of its more significant and stable temperature, stress, and pressure handling capacity.
However, the proper lubrication throughout the mechanical components prevents frictional engagement and grease. That will dynamically improve the engine’s performance without sacrificing horsepower and durability.
Advantages
- Offer decent power quality for high mileage efficiency
- Excellent to use for modern and older engines
- Better heat handling capacity prevents engine failure
- Prolong engine life protecting immature wear and tear
A Quick Overview Of 5w40
Basically, the more heat, the more the oil burns, and the more it loses efficiency. Here, the 5w40 is a blessing for most car owners, as this oil stays fresh and keeps the engine lubricated even after burning for many miles.
This fully synthetic oil will not be sticky at both low temp -13°f or -25°c and even flow fast at 104°f or 40°c high temp. So when the engine runs, you won’t think about its piston, bearings, and many other moving parts producing heat. The oil will protect those metallic components from corrosion and rust, ensuring proper lubrication.
However, sludge and deposits are other culprits that can reduce your engine oil’s thermal strength. 5w40 engine oil also focuses on this section, so it contains some added detergents which will kick them off from building up. As a result, it promotes high mileage efficiency between oil changes.
Advantages
- Superior low-temperature properties protect cold start wearing
- Higher viscosity index ensures high-temperature resistance
- Greater oxidation and thermal stability reduce oil breakdown
- Added detergents will protect the engine from damage
A Detail Comparison Between 10w30 vs. 5w40
The above discussion helps you understand the quality of 10w30 and 5w40 engine oils, but that isn’t enough to determine their differences. Here, a feature-by-feature comparison will be great to define the better oil.
Viscosity Grade
Since the significant difference lies in the viscosity index, we first focus on this point.
10w30
It comes with higher volatility in cold weather conditions. So it will turn into a little bit thicker than 5w40. But, in hot weather conditions, this oil thickness will be as great as your engine requires for proper movement. Its viscosity index is 10.7 at 100°c temp, which is absolutely alright to withstand high heat.
5w40
On the other hand, 5w40 has low volatility in the winter season, meaning it remains thinner in cold temperatures. And its viscosity index is 13.7 at 100°c, which is higher than 10w30. Simply, it’ll be less dense in hot weather.
Verdict:
10w30 is good for the winter season and 5w40 is good for summer.
Performance Level
No matter which oil you pour into your car’s reservoir. Nothing but potential performance can make you happy with your journey. And the engine oil directly impacts the performance of the engine.
10w30
As this oil doesn’t work under high pressure and stress. But, still you can get a maximum of 5000 miles or 8000 km of efficiency from the oil. Which is slightly inefficient than 5w40.
5w40
This oil can offer you around 10000 miles or 16000 km of efficiency, though it handles higher stress and pressure. But if you drive the car under extremely harsh weather, it’s better to change the oil earlier to keep your engine healthy.
Verdict: 5w40 offers you more mileage efficiency than 10w30.
Fuel Economy & Eco-friendly
As a car owner, you love to use the oil which offers you higher fuel economy.
That’s great!
But, rapidly global warming is increasing and we all are concerned about our environment. You also look at it because if we can’t reduce the warming, our life will be in danger. So we have to save the earth to save our life.
Since engine oil produces heat and releases emissions, you must focus on using less harmful and environmentally friendly oil.
10w30
The 10w30 oil has a lower viscosity grade and resists high temperatures in cold weather. So it burns more oil to cope with the temperature. The sulfated ash-releasing rate of this oil is 1.3%. The more fuel burning, and ash-releasing rate increases air pollution.
5w40
Using 10w30, your car needs lower fuel consumption to run the engine. So higher mileage promotes better fuel economy. Even lower fuel consumption will indirectly produce less heat and release less emission. Its sulfate ash releasing rate is 0.8%, which is 0.5% lower than 10w30. This is how 10w30 oil will support your pocket as well as the environment.
Verdict: 5w40 is more fuel economical and environmentally friendly than 10w30.
Compatible vehicles
There are no limitations on motorized vehicles. Some of the most common motorized vehicles are Cars, Jeeps, bikes, light-duty or heavy-duty trucks, lawnmowers, ATVs, and SUVs. These are powered by gasoline, patrol, and diesel engines and run with engine oils. But all oils are not suitable for all engines.
10w30
Any heavy-duty trucks, Nissan cars, lawnmowers, and four-stroke engines will perform great with 10w30 oil.
5w40
This oil is excellent for passenger vehicles, automobiles, and light-duty trucks, with superior protection and performance.
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FAQs
Can I use 10w30 instead of 5w40?
No, you shouldn’t use 10w30 instead of 5w40 because both the oils resist different temps and are suitable for different weather.
Can you mix 10w30 and 5w40?
Yes, you can mix 10w30 and 5w40. In that case, the oil’s exact viscosity lies in between the two viscosities. But you shouldn’t recommend mixing, as they are formulated and designed to meet different purposes.
What To Choose Between 10w30 and 5w40?
Basically, the answer is gray as it depends on many variables.
In short, your engine types, local weather conditions, and the vehicle’s load-carrying capacity are the fundamental consideration factors to choose from.
The 10w30 will be better for the winter season and heavy-duty vehicles. At the same time, 5w40 is suitable for the summer season and light-duty vehicles.
You can also use the oil by interchanging. That means if you use the 10w30. When it is time to change the oil, use the 5w40 oil and repeat this process. However, following the OEM specifications and recommendations is the best and most reliable practice.
Hello, I’m Gary. Welcome to my blog.
Complete graduation from Weber State University ( Department of Automotive Technology)
I have been working with automotive for about 17 years. I have a garage in New Jersey.
In my spare time, I love to spend time with my family. Driving new cars is my hobby.