I've got the original tires with the Nitro-fill. Leaving the garage the pressures read 26-27 psi. After about 10 miles they are reading 31. Am I better off this way or should I have a higher cold pressure and 31+ after ten miles. Could this be an indication that the tires are filled with air instead of nitrogen? Any thoughts would be great!

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I spoke with the engineers at Goodyear some time back and was told for optimum tire wear and handling the tires should be filled to 32 lbs. cold. and checked frequently since pressure will change with ambient temperatures. I did not discuss nitrogen fill with them though. I have some friends that are showing extreme tire wear using the factory recommended pressures. The Goodyear folks told me that the factory recommended pressure setting is for ride only and not tire wear. I didn't notice any real difference in the ride of the car and my tires are not showing any uneven or extreme wear.

I have an 06 with over 12000 miles and I keep the tires with the recommended 30 PSI cold pressure using normal air. The EMT stock tires do change pressure quickly, and after just 5 miles they normally go up 1 or 2 PSI. Wear has been great and the tires look like new with good ride and handling. I do have to adjust the pressures with the changing environmental termperatures on a regular basis. I have checked a few tire gauges, and found some discrepancies. I now have a digital gauge that agrees with the DIC. Had to spend $20, but after checking numerous gauge inputs, I have confidence in the DIC.

|UPDATED|10/16/2007 11:03:53 PM (AZT)|/UPDATED|

I have an 06 with the F55 suspension and the car's tire pressure indicators do not agree with my Burdon tube hand tire pressure gauge. Cold at 31 with my hand gauge gets me 28 psi on the DIC and a month later the monthly car check by On-star squawks that my tires are low. Anyone else disbelieve their DIC indicators?

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Curt Franz LeMans Blue Coupe born on Sept 15th, 2005

I agree that the DIC is inaccurate. I use a very accurate hand gauge, set the tires at 30 cold and the readout tells me 28. Go figure!

My TPS read about 1 PSI lower than my gauge. At 30 PSI cold, I was wearing the center of the tires faster than the edges. Currently running 28 cold, but I believe the important number is HOT pressure.
Here in Florida the road itself can get up to 130 F in the summer, and the tires get at least that hot. Those in cooler climates might never see tire temps that high.

Have the Dealer calibrate your on-board Tire Pressure Monitor using an accurate Pressure Guage.

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Stephen P