My low tire indicator has started coming on. Can't find a low tire. My husband said it may be the change in temperature since it is getting cooler at night.
Anyone else notice this problem?

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Comment by Beth on October 16, 2009 at 6:25pm
The pressure in my rear tires were way off.

Glad I got a gauge so I could check.
Comment by Jim VW on October 15, 2009 at 6:49am
I found the cause of my TPMS light going on frequently was due to the tire gauge I was using. I purchased a new digital gauge and the light has not come on until the colder weather lately, Once I added the correct amount of air, the light went out on it's own.

Once you are sure the tire pressure is correct, then you can reset the TPMS system. If you reset it without the propper air pressurein the tires, it will maintain the new setting.
Comment by Brabus007 on October 14, 2009 at 9:29am
~Seeing as were talking about AIR~We Best AIR This Subject OUT~

~Don't Be The Fool~Don't let them laugh at YOU all the way to the BanK~
NOTE: If you do top off your tires regularly, and it is the oxygen leaking out, with the nitrogen not leaking out as fast, what is left in your tire after many months? I would think it would be mostly the nitrogen.

Nitrogen is probably another example of an industry trying to make more money by selling you something you just do not need. Using dry nitrogen in your tires would mean that the 21% of air that is oxygen and a tiny bit that is water vapor will not be inside your tire, but remember that ordinary air is 78% nitrogen to start with. There are a number of claims of improvements due to using nitrogen...

One claim is that nitrogen reduces oxidation of the rims and the rubber as there is no oxygen or water inside the tire. Nice claim, makes sense on the surface. But I have never seen any signs of oxidation in my rims even on my currently 12 year old vehicle, never had a tire fail due to deterioration of the rubber or even heard of such a thing. A tire is likely to wear out long before rubber deterioration becomes an issue, if it was the tire companies would be getting sued left and right due to failing tires.

Another claim is that tire pressure changes less due to temperature. As long as all of the components remain a gas there is no difference in the temperature/pressure performance of pure nitrogen versus air, you get about 1psi for every 10°F change in temperature. The claim is that when the water condenses it will reduce the tire pressure. In the higher pressure inside the tire the temperature that water will condense is much lower than the same air outside the tire. It is unlikely that this is a major problem.

The one claim that seems to be something to consider it that nitrogen permeates (leaks) through the rubber more slowly than oxygen meaning that the tire will loose pressure at a lower rate than a tire filled with only air (You Still Lose Nitrogen At A Little Slower Rate). Claims are 1-4psi per month less loss meaning you will get better fuel efficiency and lower tire wear due to low pressure tires. This is easily dealt with by simply checking tire pressure regularly.

Another interesting thought... If you do top off your tires regularly, and it is the oxygen leaking out, with the nitrogen not leaking out as fast, what is left in your tire after many months? I would think it would be mostly the nitrogen.

There are some places where nitrogen is used regularly...

Racing teams generally use nitrogen to fill tires. But these teams also tune the cars to a very fine degree to shave fractions of a second off a race. Drivers claim to see handling differences with very small tire pressure changes (not being a race car driver myself this seems odd). So getting the water vapor out of the tire might make a difference in handling. These are changes that will just not be noticed in a non-performance vehicle like your SUV or minivan.

Aircraft tires are routinely filled with nitrogen, but then consider the conditions aircraft tires are subjected to. They sit on hot asphalt, with temperatures of well over 120F and a few minutes later they are at 30,000ft where the temperature might be -40F. When this cycle is reversed they are expected to survive many tons of aicraft hitting the ground. Frozen water in the tire could be a bad thing, it could freeze on one side of the tire while in flight then create an off balance tire when the aircraft lands. Just a little more extreme environment than your average passenger automobile.

Handling nitrogen is easier on an airport flightline where personnel can be trained in it’s safe use, it is usually stored in liquid form which can be dangerous to the novice. Nitrogen is already available on the flightline as it is needed anyway for pressurizing aircraft struts and hydraulic systems.

So for automotive uses you should save your money, use plain old air, and remember to check your tire pressure more regularly.
Comment by SMARTY on October 13, 2009 at 3:48pm
yes i was wondering about the light it my second signal and eah time the tire stills reads as before.
but was alo thinking why were they set (front tires) so high when the door jam says 29lbs. when checed it had 36-40 when purchased. so what the best/right tire pressure

wouldn't feel right to only have 29lbs :-/
Comment by Mark on October 13, 2009 at 11:53am
The dealer set all of my tires at 38, surprised that it didn't go off earlier. It's the change in temp Lee.
Comment by john on October 13, 2009 at 12:31am
inflate tires per spec. Press & hold pressure sensor button on dash till light on cluster flashes.
Mine was set wrong from dealer. tires were inflated to 38 psi all the way around.
this is covered in the manual.
Comment by GetSmrt28277 on October 12, 2009 at 11:14pm
Mine has started this year...again. It happened off and on and all last winter.
Comment by Marilyn Kaminski on October 12, 2009 at 10:55pm
Do you need to reset the warning indicator every time you put air in the tires?
Comment by Todd Blackley on October 12, 2009 at 9:00pm
I had this and it turned out to be a nail and a really slow leak. It's easy to check.
Comment by tommyk on October 12, 2009 at 8:08pm
yup my car did it also weather is getting colder and air contracts when it's cold just add air and then don't forget to reset the air indicator by holding the button it will flash on and off a few times then go out. now your all set to go

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