Neal’s Garage is happy to announce free nitrogen fill up for your tires. The pressure in nitrogen filled tires will change when temperature changes just as it would with regular air. However, nitrogen does not contain the moisture and other contaminants found in compressed air. Therefore, when you drive and the tires heat up – the nitrogen filled tires will fluctuate less in temperature and pressure than regular air filled tires while driving. Overall, your tires will run cooler and at a more consistent pressure than if they were filled with regular air.