So what you're saying is you run 30 psi in your tires because that gives you even tire wear? Your tires must have a really strong carcass that does not flex because the front end of your truck weighs almost twice what the rear does.

 

i have been saying 30psi since the beggining of this topic and you finally figured that out

just for you i will try 32-35 psi on of these days and see how i like it. and yes i will leave it that way for a while. will that make you feel better?

 

C'mon guys. It is just air!! Sheesh.

 

well as of yesterday it is just Nitrogen for me

for those who don't know nitrogen is better then air when it comes to filling tires up. Costco offers it to its members and since i just got a job there in the tire center, well i finally got around to doing it. yesterday i rotated, balanced, and put nitrogen in my tires!!!

 

i run 32 up front and 30 in the back....nmo problems and no crazy wear..

 

I run my stock GoodYear Wrangler RTS at 40psi

 

And the Winter Air in the tires for snow states is heavier for better traction...ask your dealer.

 

50 psi would probably be way too much, you would wear out the inside of the tire.

 

Please.... enlighten me

 

It doesn't change density as much when the tire's temperature changes. Pressures stay more consistent. Good on a race track, useless on the street where tire temps don't vary all that much. I suppose you if you had wild climatic swings it would help there too. You lose 1 psi every 10 degrees on the average tire due to the mosture content in the air (which nitrogen doesn't have).

If you wanted to be technical you would have to recalculate the baseline tire pressure since Ford's reccommendations (the holy grail) are cold (expected to cause higher pressure when the tire heats up) and with air from the atmosphere and not a bottle.

 

The pressure listed on the tire is the MAXIMUM recommended pressure. This is only needed if you're gonna haul or tow something really heavy. It's simple: More weight makes the tire sag more. Less Pressure makes the tire sag more. Too much tire sagging = friction. Friction = heat. Too much heat = tire belt separation. Hence the high pressure is only needed to combat heavy weight.

Otherwise follow what your fuel door says, or your personal preference. Anything between 32 and 35 PSI is normal. The higher you go, the better traction you would probably get, but your tires will wear quicker. The lower you go, the more the tire starts to buckle under in the middle. Resulting in softer ride, and increase wear on the outside and inner edge of the tread.

Great point Dave on tire temperatures. I consider all pressures given above to be at relatively "cold" temperatures, as in, not after 2 hours on the highway, but after driving a block or two to the gas station/tire shop.

 

give it up Dave/Julie, you are such and ***!!!




In regards to nitrogen here is a little more info. that goes along with what has been said above

I work for costco in the tire center and the way that we get nitrogen is we have a machine that takes air from a compressor and removes the nitrogen from it.

Nitrogen is better then air because during the process moisture is removed and moisture is what causes your tire pressure to fluctuate when your tires heat up.

Also a bigger advantage is the fact that nitrogen is a bigger molecule then regular air. what this does make it harder for the nitrogen to seep out of your tires, meaning that you don't loose as much PSI in your tires as you normally would.

 

I still fail to see how 30psi in the same tires gives you even tread, considering the front tires have MUCH more weight riding on them.

I'm curious as to Nitrogen being a smaller molecule than "regular" air. I assume you're talking about N2. "Regular" air is made up of 78% Nitrogen, 21% O2, and 1% other gases. It seems an individual molecule of N2 would be lighter and smaller than the N202CO2He2 etc etc etc that we breathe everyday.

 

I guess the point of nitrogen is that it is cheaply available, does not contain moisture and does not react with the rubber in the tire. To the extent to which these properties matter seems to be the main debatable issue.

I can't imagine that pure nitrogen is that radically larger than the air all around us, because the air is more than 75% nitrogen itself. We need a chemist to chime in on that.

 

nitrogen is supposed to be a LARGER molecule, not smaller. what saying before is what i have been told at work.

yes, regular air has lots of nitrogen in it. i think that basically the part of the air that is not nitrogen is causing you to loose more of your psi. that is why pure nitrogen is better.

i have a hard time believing that costco would switch to nitrogen and by expensive machines if it wasn't a lot better.

i remember reading some stuff about the plus side of nitrogen in some magazine like a year ago or so

 

http://www.cartalk.com/content/colum...tember/05.html

 

http://www.airproducts.com/pressroom...6106_sep03.htm

http://gonitro.net/intro.htm

http://www.tirebusiness.com/subscrib...;id=1055168720

http://www.tirelast.com/id15.html

 

But the point is that it's not the type of gas that is in the tire, it's the water vapor that is in it. Does a nitrogen generator automatically filter out the air's humidity better than an air compressor? Any filters or devices used to remove water vapor from one gas mixture, can't be used on the other?

 

i don't know. the machines at my costco are supposed to produce pure nitrogen without moisture, or at least very close to that.

well remember that because nitrogen is a bigger molecule it will keep you pressure in your tires the same longer