Engine oil or engine lubricant is one of the important components of a vehicle that consist of the engine (Heart of vehicle). Engine oil are of various types that help the engine to reduce friction in moving parts, helps to avoid unwanted internal combustion and keeps the engine clean from sludge. 5w30 and 5w40 are two different types of engine oil. Engine oil has the first single graded and second multi-graded.
Summary
5w30 vs 5w40
The main difference between 5w30 and 5w40 is that 5w30 engine oil has a high rate of viscosity. On the other hand, 5w40 is engine oil has a lesser rate of viscosity. These codes indicated the viscosity level of certain engine oil and ‘W’ in 5w30 or 5w40 means ‘WINTER’.

5w30 is engine oil that is made for places that have low temperatures. In 5w30, ‘5’ stands for the viscosity of that engine oil and how well it performs when the temperature will be low. ‘W’ means winter and ‘30’ stands for the viscosity of the engine oil and how well it performs when the temperature will be high.
5w40 is engine oil that is made for places that have normally low temperatures. In 5w40, ‘5’ stands for the viscosity of that engine oil and how well it performs when the temperature will below. ‘W’ means winter and ‘40’ stands for the viscosity of the engine oil and how well it performs when the temperature will be high or nearly 100 degrees Celcius.
Comparison Table Between 5w30 and 5w40
Parameter of Comparison | 5w30 | 5w40 |
Viscosity level | High viscosity | Comparatively less viscous |
Range | Viscosity from 5 for the lower temperature to the viscosity of 30 for higher temperature | Viscosity from 5 for the lower temperature to the viscosity of 40 for higher temperature |
Availability | Less available | Highly available |
Thickness | Slightly thinner | Thicker as compared to 5w30 |
Price | Expensive | Cheaper |
What is 5w30?
According to ‘SAE’, engine oil 5w30 is a lower viscosity oil that is mainly used in low-temperature areas. Places like mountain regions or places have frequently snowfall. 5w30 engine oil is a thinner oil, that provides smooth functioning of engine in low temperature also 5w30 engine oil flows fastly which helps engine avoiding combustion and reducing friction in internal moving parts.
5w30 is a type of oil that comes under the category of multi-graded oil. It is an oil that works efficiently under any condition, hence working properly in summers as well as in winters. Also in winters, its viscosity level of 5 led the flow of oil at ease and oil does not become thinner.
Moreover, in summers its viscosity level of 30 helps the engine to work smoothly without internal combustion and friction. 5w30 engine oil is generally used in diesel engine vehicles and light-duty petrol vehicles. Its viscosity from 5 to 30 helps vehicles to travel in colder places, without engine failure and makes travelling easy.
What is 5w40?
5w40 is engine oil that reduces the heating produced in the engine. 5w40 protects the engine from oxidation and helps the engine to work smoothly. It is also a crude oil that is used in vehicles that have leaded gasoline. In 5w40, the lower viscosity is 5 and ranges to 40 which helps the engine free from sludge during summer or in high-temperature areas.
5w40 engine oil is widely used in various vehicles such as transport vehicles or personal vehicles. People or traders who move quite often, face different weather at different places 5w40 engine oil whose had a good range of viscosity provides easy travelling.
Moreover, this oil has more life, that is not needed to change immediately after 4-5 months. So for avoiding this situation it is better to change to 5w40 oil for the higher protection of the engine as it creates a reliable and sufficiently thick protective film, which certify low friction, extend the life of the engine, reducing the probability of a sudden engine failure.
Main Differences Between 5w30 and 5w40
- 5w30 and 5w40 both are multi-grade oil of different viscosity.
- 5w30 engine oil is not used so much as 5w40 as it is easily available in the market as compared to 5w30
- 5w30 engine oil ranges from five to thirty viscosity levels whereas, 5w40 engine oil ranges from five to forty viscosity levels.
- 5w30 is comparatively expensive than 5w40 because 5w30 has a higher power of pumping through the oiling system. It has more efficiency to wipe off the engine parts, helps their cooling, and save fuel.
- Overall 5w40 has high viscosity than 5w30. In hot places or places having high temperature the 5w40 engine oil does not become thicker and hence avoid engine failure due to engine oiling.
Conclusion
Both 5w30 and 5w40 is multi-graded engine oil. Multi graded oil is also known as ‘All season oil’, as this oil is very versatile and can be used in winter, summers or any season. Its viscosity and range remain neutral throughout any temperature.
In earlier times single grade oil was very useful but nowadays multi-graded oil has taken its W80, W100 are some examples of single graded engine oil. Multigrade engine oil codes are like 5w30, 5w40, 2w50, etc. These codes are indicated on the pack of every engine oil.
Picking up the right engine oil is dependent on the desired protection of the engine against the wearing and thermal impact. The low thermal characteristics of these oils are the same. Both oils maintain optimal viscosity for cold engine start as well as good viscosity.
There is one unfavourable condition IN 5w30 engine oil that applies to using this oil is that, if the number of gaps in the fiction couple increases leakage may occur.
One must make sure that the front one digit should be less as much as possible (For example in 5w30, the ‘5’ is a less value). According to surveys, a lot of bike and car owners opt for 5w40 engine oil, Hence 5w30 engine oil is expensive and 5w40 is comparatively cheaper.