Are there benefits to filling a tyre with nitrogen?
The reasons why car tyres are traditionally filled with air are to improve driver comfort, reduce the weight, and improve the fuel economy of the vehicle. Some garages have begun offering a nitrogen inflation service for tyres which has left many drivers wondering why, and whether it is something that they should do.
Racing cars have nitrogen-filled tyres as, when travelling at high speed around sharp corners and under hard braking, maintaining a constant tyre pressure is essential for safety reasons. Many aircraft also use nitrogen in landing gear wheels. Nitrogen is chosen for this purpose as it is an inert gas whose molecules are larger than those of air, making them less likely to permeate the tyre wall when it heats up suddenly through use.
All tyres will lose pressure over time, no matter how new they are or how well the vehicle to which they are fitted is driven. This is because the majority of pressure loss comes from everyday stresses such as temperature variations, natural permeation of the tyre compound and valve leaks rather than punctures.
Studies have shown that nitrogen-filled tyres lose pressure at about a third of that experienced by air-filled tyres so where an air-filled tyre could lose 1 PSI a month, it would take a nitrogen tyre three months to lose the same amount.
There is a theory that putting nitrogen in tyres will improve a vehicle's rolling resistance and fuel economy due to the slower reduction of pressure but again, this is not significant and can be easily mitigated through checking tyre pressures regularly and topping up with air when required.
When debating using nitrogen vs air in tyres, there are many considerations and if cost is one of them, it should be noted that it is often is free to fill your tyres with air, however nitrogen filling garages can charge a hefty sum to drain the air from your tyres, refill them with nitrogen and then perform the necessary top-ups.
One situation in which filling tyres with nitrogen could be a sensible consideration would be for someone who planned to put a classic car into storage for a number of months. By filling their tyres with nitrogen instead of air prior to storage, they would also remove all traces of water vapour from inside the tyres, which could reduce the already-low likelihood of corrosion forming on the valve stem or wheel.
In our experience, the benefits of inflating tyres with nitrogen are so imperceptible that justifying the inconvenience and expense can be hard to do. It is generally more worthwhile investing in a tyre pressure gauge or visiting your local Protyre garage who can perform a free tyre check for you and advise on the correct tyre pressures for your vehicle. We also stock a wide range of tyres from budget brands to the major manufacturers such as Pirelli, so if you need a new tyre for your vehicle, our qualified fitters will get you safely back on the road in the shortest possible time.
