Nitrogen in tires: Do those green caps mean better gas mileage?

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Have you ever seen those little green caps on car tires? Those caps represent the fact that the vehicle has nitrogen in its tires instead of standard air. This generally is added by dealers, and is more and more commonly being added by people at home. The main reason why this is added is mileage, however that is even debated in the industry.

So does nitrogen in tires improve gas mileage? Yes, nitrogen improves gas mileage. Moreover, tire pressure loss is slower on nitrogen-filled tires. When compared, nitrogen gas filled tire escapes slowly or leaks slowly than air does. What is the end result of nitrogen-filled tires? The person who drives a vehicle gets full tire life because of fully inflated tires rolling on the road. The fuel efficiency is increased due to these reasons. So, you get better gas mileage by filling nitrogen in your tires.

How does nitrogen in tires improve gas mileage?

A simple science which you need to understand when you use nitrogen in tires. Why nitrogen is recommended for your fuel efficiency?

In common, compressed air leaks out of the tire easily than Nitrogen gas. Why? The nitrogen molecules are bigger than oxygen molecules.

Hence, nitrogen does not escape the tire for a long time and keeps tires inflated.

Salient features of the nitrogen-filled tire

Air escapes both oxygen and nitrogen through the inner liner of the tire eventually. However, nitrogen takes six times long time than oxygen to escape the tire.

The stability of compressed nitrogen is higher than ordinary air that fills the tire. The compressed dry nitrogen remains stable in high temperature during you travel on the highways. Hence, nitrogen-filled tires stay inflated with full capacity making an individual feel comfortable on mileage benefits.

The science behind nitrogen filling

A large temperature swing may lead to the leak of air in the tire. The pores of the tires help air to escape the tire. The air inside the tire expands when it gets hot. temperature swing may lead to the leak of air in the tire. The pores of the tires help air to escape the tire. The air inside the tire expands when it gets hot. Due to pressure difference, air escapes out of the tire through pores. Moreover, nitrogen is not inflammable, and so there is no chance of explosion.

What are the advantages of nitrogen filling?

Nitrogen is an excellent alternative to compressed air in the tire. Nitrogen is greener and safe to the environment with reduced emissions. The longer life of a tire decreases the chance of tire demand a lot. The tire manufacturing companies reduce the intake of raw materials for making tires thereby saving natural resources.

Due to the salient features of Nitrogen filling, the individual is benefitted a lot. Yes, he gets a long mileage, and hence his fuel cost gets decreased a lot when compared. Yes, nitrogen in tires improves gas mileage for an individual for a long period.

Do the following if:

  1. You ride a race car because nitrogen offers you the consistent pressure required.
  2. You buy a new car and want to fill in the air. Yes, nitrogen is the best choice for your car and mileage purposes.

What are the features of Nitrogen?

Nitrogen is a dry gas when compared to oxygen, and so it prevents tires from becoming rot. You shall get a wheel rust-free feature by filling in nitrogen. Yes, usually tire expands and contract due to alternatives of heat and cool status. Due to this reason, tires generate moisture which does not happen with nitrogen gas.

Rubber rot problem is not present if you fill the tire with nitrogen gas. Hence, your tire life span is extended to cope with your demand and expectations.

Yet an advantage of using nitrogen gas filling

Do not wait to fill the tire with nitrogen when you travel. The under-inflated tires are not safe for your vehicle and you. So, you shall top off the tire with air until you arrive at the nitrogen station on the way. If your tires are properly inflated, you shall enjoy the travel, and so there is no difference in riding comfort with air or nitrogen.

Frequently Asked Questions

Can I fill my tires with nitrogen at home?

While it is not super common quite yet, it is completely possible to fill your tires with nitrogen at home! However you will need special equipment, so most people still find it much easier to take the hit on mileage and fill their tires with normal air at home.

How do you tell if you have nitrogen in your tires?

Tires that are filled with nitrogen generally will have green caps on the valve stem! That said, most people won’t be re-filling their tires at home with nitrogen so that can get diluted down over time, and may not perfectly represent this.

What happens if you fill tires with helium?

While most people would want to believe that their vehicle would be lighter, and get better gas mileage if helium is added to their tires, this just isn’t the case. Helium may allow a party balloon to float, however the ratio of a vehicle to the characteristics of helium are negligible.


The above details may enhance your brain to fill in the tire with nitrogen. Yes, it is a good idea when we delve deeper into the scientific evidence behind it. You need not worry if you want to fill in with nitrogen for the first time.

You shall go ahead because the nitrogen filling station mechanic knows the technic by using the pumping machine. Indeed, nitrogen filling is a clever idea.