Nitrogen in tires, where to fill up?

SouthArk370Z

Most tire shops around here (S Arkansas) carry N2.

Doesn't make sense to me, but you may be in a more remote area than I am.

Not much. There are some minor advantages to N2 (see posts above - IMNSHO the biggest one is TPMS sensor corrosion and that shouldn't be anything major), but just adding some air to your N2-inflated tire will not do any damage (assuming it is reasonably clean and doesn't contain too much oil or other contaminates). Only 20-something% of what you're adding is not N2 and you're only adding a small amount, so you're not diluting it by much.
There will more than likely be some water entrained in the air (how much depends on the compressor setup, humidity, &c), but it should be minimal and the N2 that is already in the tire will absorb some of it.
Unless you are obsessive about having 100% N2 in your tires, all you need to do is have the tire(s) bled down and refilled with N2 at your convenience. If this is the only time you've added air, I wouldn't give it a second thought.


Edit: Neither Goodyear nor Hankook even mention N2, much less recommend it. YMMV

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