Difference Between 5w30 and 5w40

What is 5w30?

5w30 is a type of engine oil. Engine oils are significantly used to generate work for the automobile to work efficiently. Engines are all made of materials that produce a large amount of friction. In between, all these engine oils are used to lubricate and produce less friction.

This helps in better fuel combustion. This lessened friction helps to produce more work. That is why engine oils are needed for automobiles. Viscosity is the resistance offered by the liquid.

Whenever there is a movement inside a liquid due to external forces, the liquid tries to resist that force from changing its shape, velocity, etc. This property of liquids is called Viscosity. Viscosity can be of two types;- Dynamic and kinematic.

Dynamic Viscosity is the ratio of the resistance of a liquid to the flow of liquid. When dynamic viscosity is divided by the density of the liquid, it is called kinematic viscosity.

With the increase in temperature, viscosity also increases. Thus, this increased viscosity increases the efficiency of oils. 5w30 has a viscosity of 5Pa-sec at minimum temperature and 30Pa-sec at maximum temperature. The kinematic viscosity of 5w30 differs within the 9.3-12.5mm²/s range. The dynamic viscosity of 5w30 is 2.9mPas.

What is 5w40?

5w40 is a type of engine oil with a viscosity between 5 to 40. This engine oil offers a viscosity of 5Pa-sec at minimum temperature -25 degrees Celsius and 40 at maximum temperature of 35 degrees Celsius. Kinematic Viscosity is the ratio of resistance to the flow of liquid.

This ratio for 5w40 is 12.5 to 16.3 mm2/s at 100g. The ratio of kinematic viscosity and density of the same liquid is called Dynamic Viscosity. For 5w40 engine oil, dynamic viscosity is 3.5mPas.5w40 has more viscosity than 5w30.

This higher viscosity prevents it to work at high-temperature differences.5w30 can be used at both low and high temperatures efficiently. Therefore,5w40 is not very efficient in working at high temperatures. This adds to its drawback.

This is the exact reason behind 5w40 being used in less amount than 5w30. As 5w40 has less used. It’s cost less. This is what makes it a common choice in automobiles. 5w40 works at a temperature ranging grom-25 degrees Celsius to 35 degrees Celsius.

As 5w40 has more viscosity the thickness of oils is more. This thickened oil increases fuel consumption as it takes more time and fuel for combustion to take place properly.

Difference Between 5w30 and 5w40

1. 5w30 has a viscosity ranging from 5 to 30Pa-Sec.On the other hand, 5w40 has a viscosity ranging from 5 to 40Pa-sec.
2. For 5w30, the range of kinematic viscosity is 9.3-12.5mm²/s whereas for 5w40 it is 12.5 to 16.3 mm2/s at 100g.
3. 5w30 has a dynamic viscosity of 2.9mPas.In the case of 5w40, the ratio is 3.5mPas.
4. 5w30 is in temperature ranges from -25°C to 25°C.On the other hand temperature range for 5w40 is -25°C to 35°C.
5. 5w40 is cheaper than 5w30 with the rate of Rs.230/L. The cost of 5w30 is Rs.400/L.
6. 5w30 is more used and hence readily available in comparison to 5w40.