Originally Posted by rmw

This was a big topic of discussion on another forum a few years back and speaking as someone with a Chem/Physics degree and who has worked a lot with compressed gasses 99% of the claims for using N2 to fill tires is pure hogwash and I think I've heard every claim that's been made.

Less pressure loss: Consumer reports needed to redesign their study because the physics aren't there to support even the little bit improvement they reported.

Preserves Tires: Again, think, tire don't rot from the inside out.

N2 doesn't expand so tire pressures remain stable: That requires re-writing the General Gas Law and is pure nonsense.

Airplanes use N2: True but for two reasons. One it prevents the possibility of moisture from collecting in tires and freezing at altitude and second N2 doesn't support combustion.

There are a lot more claims made, but you should get the idea. The only good thing about putting N2 in your tires is that its good for the dealer's bottom line.