I have a question if your tires have had compressed air in them before as most or all have. Would'nt you have to get the moisture out of the tire before you fill it with Nitrogen. I work in the HVAC field and for refrigeration system were it's very important to remove moisture. We use nitrogen to test systems because it dosn't carry moisture but we use vacume pumps to pull the systems down to like 500 microns to be sure all the moisture is removed. But then again I guess it's not as important to remove all the moisture from a tire and I'm sure the Nit. filled tire would be drier than with air.:57: