Good question. I called around to a few tire shops and found at that several of them are already offering nitrogen for a $2-$4 a tire with lifetime refills. The Goodyear place and Costco was free. Supposedly they have a machine that removes the air in the tire and replaces it with nitrogen without dropping psi low enough to bust the bead.

JCL & Hayaku,
Really appreciate the good insight on both sides. Thanks :thumbup:

i called costco, they confirmed having the nitrogen machine but only fill tires if you've bought tires from costco. good year store doesnt offer such service, neither does america's tire. i was told by a friend to drive to the back of costco's tire shop and slip a 10 for one of the guys back there to do the tires...i will try...

thought i share a pic from the m3 crowd that uses nitrogen to control psi growth

http://members.roadfly.org/Irrenarzt...Tire%20vac.jpg

thats how you purge regular air out of the tire before you fill it with N2.

wow, coool! ha ha ha ha
hey that looks like a rogue engineering spacer right there, just like mine!