I don't know if anyone here has tried this yet, but my wife has an '04 Pacifica and she just had nitrogen put into all of her tires. It supposed to make the tires last longer, and maybe it does. However, her Pacifica now rides like it has NO suspension!! Before the nitrogen it rode really well, but now it rides like a brick!! You feel EVERY little imperfection in the road. She's tried to get me to put it in my S500 tires, but I think I'll pass on that offer!! I think I'll just let my tires die a natural death!! She paid $40.00 to have that nitrogen put in, and the ONLY good thing about that is if she has a flat, they'll refill the tire for free. I guess if you live where the roads are perfect, nitrogen would be a good idea....but not in MS!!