Thread: Nitrogen tires
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Old 08-12-2011, 08:20 PM   #26 (permalink)
oil pan 4
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Originally Posted by oil pan 4 View Post
You can search and find web sites claiming that nitrogen in your tires will cause pressure to bleed off 40% to 60% slower. The standard time frame they use is "between oil changes" so I take that as every 3 to 6 months. It should be checked every month.
I said that earlier. Do you not know how to search google?

Here is the #1 google pick, top of the page:
Nitrogen in Tires : Information about Nitrogen Tire Inflation News, Benefits, Generator Dealers, Location Finder & More
That is one of the many links that will come up claiming reduced pressure drop over time and increased fuel economy.

Also I remembered I saved some of my really old data collection via an email folder when talking about varrious things with my engineer friend.

Here is some of what I saved toward the end of the tests:

The car will not be driven, maybe at then end of the day I might take it for a spin to warm up the tires for one last measurement.
So far as of [Jan 13, 2007], 0913 eastern time my temp and pressure measurements look like this.
Both tires adjusted to 33psi.
Left Rear temps:
Tread, 56.4'F
Side, 59.9'F
Rim, 56.5'F
Right rear temps:
Tread, 56.3'F
Side, 58.9'F
Rim, 55.5'F

Now we wait for Boyle's LAW to do the rest.

As of 1115 EST
Left Rear (in the sun)
PSI 34.5
Tread 72.2'F
Side wall 96.6'F
rim 75.2'F

Right rear (shade)
PSI 34
Tread 67.2'F
side 67.5'F
rim 64.5 'F

1212 EST

Left rear (still in the sun)
PSI 35
Tread 73.9'F
Side 97.7'F
Rim 77.1

Right rear
PSI 34.5
Tread 70.4
Side 74.2
Rim 67.7

1735 EST

Left rear (after a 4 mile drive)
PSI 36

Right rear
PSI 36

That is a sample of the most complete and detailed data I managed to save. We did this on and off for months. Turns out I didn't save very many of those emails.
He ran the same test on his truck, with out the detailed temperature readings and saw almost the same result.

Then on August 21, 2006 I completed a 1,200 mile road trip:

Well I just got back form that 1200mi trip this weekend. Ended up going form NewportNews VA to NY,PA border then to Roanoke, VA then back to NewportNews.
I had the [updated: now exwife] + 100's of pounds of s*** she had to have + K-9 = about 400 more Lb's then normal.
I got 24mpg.
also brought the craftsmen temp gun to do the tires.
Tires were normally 20'F (for side wall) to 25'F (for tread) hotter then the road and over 30'F hotter then the air temp.
I don't think it makes your tires run any cooler.
I took readings 8 or 9 times, and it was hoter then the normal for air tires.
I'm glad I didn't pay for getting the tires filled with nitrogen.

On a side note that was a really horrible trip and was one of prime factors that helped put the x in exwife and I had all but forgotten it till now. Thanks....

Most of the emails were about unchanged fuel milage, my tire with a slow leak. I can say for sure the tests when from late june, 2006, when the first email was sent telling my friend I was gathering a data set for an Air Vs. Nitrogen tire test. The first day of nitrogen tire tests started August 2, 2006. Some time that november the test expanded when I took his truck into work and nitrogen purged and filled his tires for free also. And we ended anything that resembled data collection Feb 27, 2007 when we concludeded that putting nitrogen in tires wasn't going to do you any good so long as you replaced your tires every 4 to 6 years.
He logged almost 15,000 miles from november (thanksgiving if I remember right) to Feb 27, his were nearly all high way miles.
I logged less than 5,000 from August 2006 to Feb 2007, all city miles but for the one road trip.

I still use nitrogen in tires since I log so few miles I could keep a set of tire for longer than 6 years.

Last edited by oil pan 4; 08-12-2011 at 08:40 PM..
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