Need tester for Over inflating tires

adamsgt said:
When I bought my last set of tires from Costco, they used nitrogen to inflate them. The service manager told me that because nitrogen was an inert gas the tires would not heat up or lose pressure like a tire filled with air. Anyone out there confirm or refute these claims?
Click to expand...

All sorts of claims on nitrogen but I think it may retain pressure better because of the larger size of the molecules compared to air...

A tire will not heat excessively unless the pressure is too low or the load excessive... it is the excessive flexing of the tire that causes heat buildup.
 
And some more things to worry about
Newer Vehicles with the Tire Monitor will NOT allow higher pressure (installed)unless you want to look at the dash light for ever! this also applies to the underinflated tire as well, as it will bring on the dash light.
See the wide or big tires that are put on most trucks, those are killers of fuel mileage, also REMEMBER when you change tire size you MUST re-flash the onboard computer to include the different diameter or your Speedo WILL be off AND the engine performance will be somwhat degridated.
Ya want better mileage??? buy less cylinders, and the Manual transmissions.

OBAMA is FULL of IT.
OH and did I say that overinflated tires WILL shake the vehicle to death, along with going to heavier ply/load rating, YEP

Clarence
 
Nitrogen may be a gimmick

adamsgt said:
When I bought my last set of tires from Costco, they used nitrogen to inflate them. The service manager told me that because nitrogen was an inert gas the tires would not heat up or lose pressure like a tire filled with air. Anyone out there confirm or refute these claims?
Click to expand...

The claims about nitrogen not heating up and expanding are bogus. Why not put helium in you tires?

Gas expands due to temperature at the rate of 1/496 th. of its volume per degree fahrenheit and that is a law (scientific). That is based on absolute zero being -459 degrees and freezing being 32 degrees Fahrenheit. Assuming that the gas in your tires are in a confined space, which it isn't, you can see why the pressure increases as much as it does.

I was told by my tire installer that the inert nitrogen gas in the tires would cause the tires to last longer. He just laughed when I asked him what the air on the outside of the tires would do.

There must be an advantage to use Nitrogen in your tires. I paid $25 for them to put in in mine. When the tires heat up the pressure still increases. Go figure.

Concho Bill
 
Bill Wynne said:
There must be an advantage to use Nitrogen in your tires. I paid $25 for them to put in in mine.
Click to expand...
Well, you made somebody's life just that little bit more comfortable. :rolleyes:

Thinking of our main interest & the use of nitrogen there, maybe there's some advantage to having a dry gas in the tyre. What is the coefficient of expansion of water when it converts to steam?
 
John,

The water inside a tire is already vapor (steam) so there is no state change that would alter the ideal gas law. Tires with liquid water inside are hard to balance and work best on tractors. Besides, very few tires will reach 212 degrees on the street unless they are very under inflated. Tires usually die from heat as a result of under inflation.

Greg
 
If you are serious and not into cars:

If you are serious and not into cars:

Tire pressure should be determined by the shape of the tire as it meets the road. Pressures printed on the sidewalls are maximums affected by lawyers to avoid law suits. It is like loading a 38 Special to market. A lawyer will tell you to load it based on legal suits rather than the specific gun and the pressure it will handle. Example: If you have a pickup with a heavy, big block engine and a 4x4 front axle it will need more air pressure in the front tires than the rear tires with that empty pickup bed. There should be just a slight bulge where the rubber meets the road when you have the right inflation. Under inflated tires will heat up and also wear the outside tread, while over inflated will burn out the centers and ride hard. If your tires get hot to the hand on an average day they may be under inflated. I inflate tires based on how they look as they meet the road, how the vehicle handles and the heat produced on the highway rather than the maximum the tire guy has to put in them by law. It is like loading a 38 Special. A lawyer will tell you to load it based on legal suits rather than the specific gun and the pressure it will handle.

Every time you apply the brakes you have wasted fuel used to move the vehicle! Time the lights with your speed so you avoid braking and drive at an even speed. Drive at speeds where wind resistance is minimized (60 rather that 80 MPH) when possible :eek:, and in away that you brake the very least for lights, traffic, etc. Jack rabbit starts that have you braking for the next light are for teenagers where Dad is paying for the fuel.

Keep your car tuned!

On small engines don't use the AC under 45 MPH if not needed, open a window. Over 45 MPH. the AC will use less fuel than the drag of open windows.
 
Dennis Sorensen said:
At highway speeds you will blow an under inflated tire up much quicker than an over inflated tire... it flexes too much and heats up way to much and fails due to the flexing and heat buildup. Over inflated will give poorer traction but it will not heat up that much... over inflation does not cause heat buildup. It will run cooler if anything.

Slightly over is much better than slightly under in my opinion... driving for 53 years now... never blown a over pressured tire...
Click to expand...

I don't think anybody is suggesting under inflating tires, rather over inflating them. I've blown over-inflated tires.
 
Mr D, I've noticed, like nodes when loading, my truck has certain speeds where it gets the best fuel mileage. It does best at 58 mph, then does progressively worse until it finally picks back up at 75 mph. It gets about 17 mpg at 75, and 15 at 70. Last time I checked, it was getting 19 at 58 mph.
 
Nitrogen in the tires !! Darn, here I was thinking that if I used helium I would get better mileage since it is a lighter gas!!! Good thing the balloon company was closed otherwise I would have wasted my money.
 
tylerw02 said:
Mr D, I've noticed, like nodes when loading, my truck has certain speeds where it gets the best fuel mileage. It does best at 58 mph, then does progressively worse until it finally picks back up at 75 mph. It gets about 17 mpg at 75, and 15 at 70. Last time I checked, it was getting 19 at 58 mph.
Click to expand...

Likely a combination of wind resistance and hitting the RPM power curve just right where you are producing the most H.P. for the least fuel.
 
Man and Machine

If we listen to and get in-tune with our mechanical drive componets and pay attention to the reaction and feel of our steering and suspension componets, in essense become one with our machines we will always maximize their efficency.

I'll never understand how some of the fellas in the machine shops I've worked in would'nt change out a tool until the machine crashed and burned :eek: not to mention all the "out of spec parts" that were produced prior to failure. :mad:One can tell in an audiable sense the sound of a dull tool as it tears the work as opposed to actual machined cuts. What's more amazing is that they keep their job's :eek: :confused:

I'm deaf as h*ll, and old to boot, yet my machines, gun's and songbird's talk to me and I hear them just fine, it's those "other" voices I keep hearing that concern me! :confused:
 
Last edited by a moderator:
This thread has the largest collection of old wives' tales that I've seen lately. This is a subject that tends to bring out the unfounded opinions stated as fact more than usual.

Nitrogen makes up 78% of our atmosphere. Do you really think that replacing some of the oxygen in your tires with nitrogen is going to have any affect at all? They don't change your tire in a pure nitrogen atmosphere. You will always have a significant amount of oxygen in your tires unless you drain and refill them with nitrogen many times.

Many auto manufacturers recommend a lower pressure than the maximum shown on the sidewall. I can guess this is for a softer ride but have no real knowledge. The maximum pressure is a crapshoot that is arrived at to cover any vehicle in any climate at any load up to max on any roads. Stating that inflating tires over max by some amount is a death wish of some sort is presumptuous. Under-inflation is a much more dangerous situation in almost every instance. The tires on my Prius have a stated max pressure of 44 psi. The manufacturer says to fill them to 35 in the front and 33 in the rear. I use 42 and 40 which has shown to increase my mileage by 5 mpg countless times. If the dealer changes my pressure to the recommended while I'm in for my free oil change, I can tell in just a few miles because my mileage readout starts to drop for no apparent reason. My lifetime average in the Prius is in the mid 50s over 104,000 miles.

Testing in many vehicles has shown that the wind resistance caused by rolling down the windows uses substantially less energy than running the air conditioning. I have proven this to myself on my car. A bogus statement was made back in the energy crisis of the 70s and it has been quoted as fact many times ever since.

Wind resistance at 70 mph is double that of the wind resistance at 50 mph. The energy required to overcome the increased resistance is four times that of the lower resistance. Wind resistance is only a part of the resistance puzzle, which includes rolling resistance and pumping resistance and other frictions within the drive train. To save gas, slow down.

I could go on but I just realized that I'm again trying to inject facts and accuracy into a discussion that has a larger goal of killing time while shooting the breeze with friends. It is one of my many character defects. To those I may have ticked off, I apologize.
 
Last edited by a moderator:
RayfromTX said:
Wind resistance at 70 mph is double that of the wind resistance at 50 mph. The energy required to overcome the increased resistance is four times that of the lower resistance. Wind resistance is only a part of the resistance puzzle, which includes rolling resistance and pumping resistance and other frictions within the drive train. To save gas, slow down.
Click to expand...

Odd....my truck doesn't get the best mileage at slower speeds. Simply because we have a thing called gears.
 
I own an idependent Lexus repair shop. Nitrogen in tires main benefit would be larger molecules = slower tire pressure decrease due to natural permeation due to porosity of rubber. Our regular customers come in at 5,000 mile intervals. Tires with air lose about 3-4 psi in this amount of time. Nitrogen is averaging 3-4 psi in the same interval. As far as I'm concerned it's a gimmick. I certainly wouldn't buy a $5000.00 nitrogen machine to make it back $25.00 at a time. I hope they're really putting nitrogen in your tires if you're paying for it!
 
Bushmaster,

I really don't know, but don't they just purchase a bottle of nitrogen and put it in tires? And I too am pretty sure that it is a gimmick.

Concho Bill
 
No Bill, it's a nitrogen generator, $4500-$5000. Looks like a freon recovery machine but green.
 
What's wrong with you guys? Get a one cylinder diesel pickup like me and stop wasting fuel: :D


ChineseTruck.jpg
 
You must log in or register to reply here.
Back
Top