The 19% oxygen that is in air does not cause deterioration of the inside of the tires. Tire damage is from ETERNAL ozone and ultra-violet light. IF you put 'wet' air into a tire, it is possible that some water will condense in cold weather (and even freeze) and so COULD cause corrosion of the rim. Always let some air out of the hose before puting it on the tire to ensure it is not full of water.

Jet aircraft use very high tire pressures (350#) ,and any moisture in air will condense at the -70F temps at which they fly and cause imbalance and virbration on landing--as well as substantially greature pressure changes. Its the water, not the 19% oxygen.

Because the rubber in tires continues to 'vulcanize or cure' after manufacture, it gets harder and more brittle with age, and builds up more heat from flexing--which all mean it will not pass the speed and load rating tests and will fail most likely. I personally put 4 yrs max on tires that I drive on the freeway. They may look great, but will not take the heat and stress. MIGHT Work fine around town though traction is way down--and with the high cost of even a minor accident, tires every 4 years seems pretty cheap to me.

think of all the tractor trailers out there with re-tread tires on them, how many miles /heat cycles are on them? they get exposed to all types of weather and who knows how many years old they are. holy crap we share the road with them?

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2003 audi A6
2002 porsche boxter
1989 jeep grand wagoneer
1987 m/b 420 sel
1966 vw type 1
1965 mustang "a" code gt

Yeah, so!!!??? How about all the truck tire caps you see littering the freeways. I've seen one disintegrate as I was about 100 yards behind approaching in the left lane to pass.

There was so much debris hitting my car I had to back off and follow at a distance, and I started weaving and flashing my high beams. The driver finally figured out the deal and began to slow down to pull off on the shoulder.

Duke