How often should I check tires?

About once a month should do it unless you have a major temperature swing.

 

Come on, I dare someone to bring up Nitrogen so we can start that debate again. Oh shoot, did I say "Nitrogen"?!?

Tom

 

several tire stores offer to fill your tires with nitrogen...for some reason...not quite sure why to be honest with ya...

some say it makes car ride better. now before ya spend any money on this quackery, keep in mind, that normal air is around 80% nitrogen, so you would not be getting a significantly different mix of air...

 

Are you being sarcastic? If so, disregard the rest of this post.

Many companies that sell and service tires are "recommending" nitrogen to fill your tires with like they do on aircraft. Their reasoning is usually as follows:

Pure nitrogen doesn't expand like regular compressed air since nitrogen is a very stable element that does not undergo major expansion or contraction when exposed to varying temperatures.

Pure Nitrogen molecules are larger than oxygen molecules which makes it harder for the nitrogen molcules to escape through the rubber of your tires unlike the smaller oxygen molecules.

Of course, using nitrogen to fill your tires costs more since they have to buy a special machine or bring in bottled nitrogen gas (not liqiufied nitrogen, major difference).

Many people on here have differing opinions and reasons for being for or against this. I personally am against it for multiple reasons:

Our cars do not typically undergo the stresses that aircraft tires (which are filled with nitrogen) do. First our tires do not go from an environment of 100+ degrees F on tarmac to 30,000 ft and ambient air temp of well below freezing in a matter of mere minutes; only to then return to a very fast heating cycle as the aircraft lands and slows down on the runway at arrival. Not to mention the changes in external air pressures from ground level to cruising altitude and back (ever wonder why they say no aerosols in checked baggage?)

Secondly, normal compressed air is something like 78% nitrogen already and I think 12% oxygen with the rest being hydrogen, helium, CO2, etc. By my logic then, once all the "too small molecules leak out my sidewalls (as the advertising says will happen). I can simply add more compressed air which would further increase my nitrogen percentage and costs me little to nothing to obtain (other than elctricity to run a air compressor).

 

I went to bed last night pretty early. But then had a dream for some odd reason that the tires in my car were low on air, I guessed 30 psi and 28 psi. So I woke up and checked. Yup, they were at 30 and 28 because I havent checked them in about 7-8 months (was out of the state for 3 months, so I didnt drive the car during that time). Its probably safe to check every 3 months, although every month cant hurt.

 

Or, whenever you dream about them, whichever comes first.

 

I think the manual says to wait 3 hours for the temp to come down although I have no idea how accurate that is. I went ahead and got the pump. I can air up the tires in the garage; plus i can carry it around with me for other emergencies like jump starts.

I've been running my tires (Bridgestone Turanzas) at 42/40 for 10K miles now and have noticed no ill effects. I'm sure there are others here who have more miles under their belts.

 

np...measure TP first thing in morning. go where you need to. re-measure, add appropriate amount...call er good... close enough.

u will find, not much diff unless it very hot day.

#1 characteristic of LRR Tires

 

Nitrogen is no more stable than oxygen or any other gas that closely follows the ideal gas law. Nitrogen expands and contracts with varying temperatures every bit as much as compressed air. Water vapor, on the other hand, is not an ideal gas. Nitrogen or compressed air containing water vapor will tend to expand and contract more with temperature.

Pure nitrogen molecules are smaller than oxygen molecules. The rate of diffusion for nitrogen is slightly higher than that for oxygen, allowing nitrogen to escape more rapidly. Of course, the relative partial pressures on the inside and outside of the tire will be the controlling factor.

Tom

 

It is the consensus among many on this site that having your tire pressure at 42/40 will increase your MPG. I think it helps with handling, and tire longevity, as well.
As long as you do not exceed the maximum PSI listed on the sidewall of your tires (mine say 44 psi), I cannot see any disadvantage at all.
Of course, if you have someone else rotate your tires, you'll probably have to readjust your TP, since tire jockeys are obligated to obey the little plate inside the driver's door.

 

you can (in relative safety) go up to 150% of rated maximum. pressure ratings are for tires at like 68ºF or something... much higher tire temps and the resulting increase in the tire pressure is accounted for

 

I have read here on the site that the ride will not be as soft. Handling may be a bit different. Haven't tried it yet myself so this is just ?readsay? hearsay!

 

best thing is to check them first thing in the morning before driving.

 

I read once, at a place that seemed credible though I do not recall where, that "cold" in a tire pressure context meant "driven not more than one mile in the previous hour".

The beauty of it is you don't need a home inflator, only a pocket gauge. A nice digital one from Accutire is about $6 at Target or Amazon. Take the readings at home before you drive anywhere, note how much you need to add, then some time that same day drive to your favorite inflator and add that amount regardless of what the inflator gauge reads initially.

Disadvantages of higher pressures include harsher ride, which can rattle the car more if you're not careful about potholes et cetera, and a possibly noticeable change in handling. It didn't take me long to get used to these, and it does noticeably increase MPGs.

 

Back in the day, 6 years ago, when I went shopping for new tires for the X-Type I ran across a website advertising nitrogen. They had all these plans and talked of nitrogen fill stations everywhere. They even had a video of 2 cars going around a test track and the car filled with nitrogen went equivelent to 100,000 miles on a set of tires. I don't see anyone driving around in circles for 100k miles just to see how far a set of tires will go. But then again you never know, some people don't have much to do. Anyway, they were talking about how the oxygen in the air degrades the rubber abd causes the tires to wear more, nitrogen not having this effect. I'm at 3500 miles right now and am lucky enough to work around an abundance of nitrogen. So, I will take on this test to see how far I can drive on a set of tires. Filled them up yesterday, 44PSI, and we'll see what happens. Now if only I can keep Toyota from re-filling my tires when I go in for service....

Free nitrogen for all, come and get it.

 

How did you go vacuuming out all the oxygen rich air?