Given that air is composed mostly of nitrogen, it makes sense that air and nitrogen expand and contract with temperature at the same rate.

The only benefit of nitrogen is that it is dry. Dry air vs dry nitrogen, there is no difference. The issue is that many unmaintained air compressors have wet air, and it is the moisture that is expanding and contracting, not the air itself.

As to BMW not endorsing it, well, neither J.Belknap nor I endorse it either. That doesn't make it bad, it simply means that we don't see reasons to come out promoting it. Maybe BMW is the same, becaues if they do endorse it all their dealers may well send them a bill for nitrogen filling equipment, plus thank you notes for making them purchase it for no good reason, but simply due to their endorsement.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
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2003 X5 3.0 Steptronic, Premium, Titanium Silver
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