Question on Trailer Wheel balancing

[RMccord]

I believe I read here were the trailer units tires are not balanced from the factory. Is this correct?
If so wouldn't that also increase the potential of a malfunction, heat build up certainly poor wear and tire life.
If they are not balanced are you folks getting yours balanced.
I know Costco inflats theirs with a gas other than air as it is more stable but only on tires they sell and install. I wonder if other tire companies do so. The reason I was told was because the gas is more stable and you don't get pressure increases and decreases as you do with air.

[Glenn and Lorraine]

I do believe in balancing all tires. Having said that I must admit I have not balanced the Monty's tires BUT I am constantly watching my tread wear for anything irregular. At this point everything is fine.

As I said in another response to one of your posts, "I spent many years and my brother still is in the tire business" and in all those years neither I nor my brother nor anyone of his employees have ever heard of a gas other than air that is more stable. This to me sounds a bit bogus and how has Costco kept this special gas such a secret known only to them and their customers. Once again I say, if you want a second opinion go to any reputable tire shop and ask them.

[sreigle]

I had them balanced on the middle two of our four fifthwheels. I don't know if it is really necessary or not. I would think so but our tire wear is nice and even since the axles were replaced and we got them aligned. So long as it remains that way I'll not have them balanced. Like Glenn, I think it's better having them balanced and will watch to see if we need to have that done.

If you have them balanced be sure they do not jack the rig up by the axles or you'll have a big tire wear problem from bent axles. They need to jack the rig at the spring plate.

[Montana_738]

RMccord,
I have a question concerning the gas versus air.
# 1 what kind of gas is it, or is this bogus?
#2 if it is some sort of gas what if you travel to a higher altitude and stay for a lengthy time, you check your air pressure, how do you compensate the difference, with air? I don't know much, but this sure don't seem logical to me. Probably a new sales pitch.
I knew a guy who owned a window washing business and he said his customers would ask for scotch guard to be put in the water to wash their windows with. He said he would add TSP to the water which would remove all the greese and crud from the window and stay cleaner longer, but it wouldn't prevent stains. He braged how he charged them extra money for nothing. I guess all's fare in love and war.

Bill

[Montana Sky]

I have had my wheels balanced and so far the tread wear is great. Keep the tires air pressure at 80psi year round, and have no signs of trouble. The one thing that has me concerned now is that Les Schwabs tire center picked up the coach under the axle. Thanks for the tip Steve, will be keeping a close eye on them to make sure they are not bent.

[Glenn and Lorraine]

Steve is right on the money. DO NOT jack your rig up on the axles. The axle housing is not built to carry the weight. The axle can bend at the jacking point throwing your tires out of alignment. Only jack where the spring plate is attached to the axle as this is the strongest point and was designed to carry the weight.

[rlwhit]

Re gas im tires. Aircraft tires are filled with nitrogen. Can you imagine putting air in a tire and going to 35,000 ft. Big bang.

[Bill Hill]

rlwhit,
I'm not sure I understand why nitrogen in the tires would make a difference at altitude. It's the reduced ambient air pressure at altitude that increases the differential between the pressure inside the tire and outside, isn't it? Why would that be different just because the gas inside is different? Thanks!

[rlwhit]

Bill, I could be wrong as I was only a pilot, but the nitrogen does not expand like air does at allitude. I recall the struts were also serviced with nitrogen.

[kdeiss]

Their is a lot of tire dealers now using nitrogen.When I replaced my tires I had them balanced An out of balance tire and wheel can damage your wheel bearings.I would recommend

[RMccord]

Yes it is Nitrogen gas. For the reasons previously mentioned. They will not fill tires they do not install.

[RMccord]

Here is some reasons to use Nitrogen for your tires. Several actually.
1. Nitrogen molecules are larger than air molecules and therefore migrate through the tire slower and takes much longer for a tire to loose pressure that way.
2. Nitrogen inflated tires run cooler as it does not heat us and expand as much or as quickly as normally inflated tires do.
3. Because of #1 above it also retards oxidation of the tire better than normally inflated tires.
4. Nitrogen is stable and does not exhibit the problems normally inflated tires do with respect to expansion in higher altitudes and temperature variances. Temps will increase with driving but very marginally
There are many tire companies now offering nitrogen and my local one here will inflate it for $3 per tire.
The cooler running may help extend tire life and potential problems.

[RMccord]

Oh and if you need for some reason to top it off at some point you can use normal air at any station to bring in line with pressure you need. I am calling Doran to insure their monitors work with nitrogen. Will post results

[RMccord]

I'm baaaaack.
Yep the monitors work fine with Nitrogen per the Doran rep. at 866-816-7233

[Bill Hill]

Bob,
thanks for all the info. I can see going to the nitrogen fill when I change out the tires, although that should be a while since we've only got about 5K miles on, rig's only 8 months old. Glad to hear that it will work with the Doran monitor, we really like ours.

[Montana_139]

I don't understand what the advantage is with nitrogen:
1. Air is 80% nitrogen.
2. All gasses are subject to the same expansion and contraction with temperature or pressure changes. The equation is PV=NRT:
P is pressure
V is volume
N and R are constants
T is temperature (Referenced to absolute zero.)
For example:
If you double the temperature and hold the volume constant the pressure will double. This is true for all gasses, unless my memory of physics is faulty.

Glenn

[RMccord]

Glenn:

I cannot fault your thinking but I do know that the aircraft industry uses nitrogen exclusively to inflate their tires because of this. If there were no difference then I feel certain they would save money where ever they could by just using nor air inflation. I am just passing on the information provided to me.

I intend to switch myself asap. If it just kept the tire cooler and pressures more even alone I would be happy to change. Also the tire dealers that provide it will deflate and inflate your tires to nitrogen for about $3 at least her where I live.

[Montana_139]

RMccord,

Here is where I start guessing. The 20% oxygen is air may contribute to oxidation of some of the materials inside the tires at very high temperatures. Nitrogen is inert. It will not react with anything.

Glenn

[Countryfolks]

This is a quote from this site which, apparently, is an engineer forum.
http://www.eng-tips.com/viewthread.c...=120996&page=1
"Helpful Member!Helpful Member!Helpful Member!Helpful Member!pisgahchemist (Chemical)
20 Jun 05 16:39
The question about nitrogen in tires has come up in other lists on the web as well. Let me clarrify a few points.

1. Air is 78% nitrogen, N2, and 21% oxygen, O2. So even if you put air in the tire, it's already 78% nitrogen. Many of the so called nitrogen generators don't produce much more than 90% nitrogen.

2. At relatively low pressures (ie tire pressures) N2, O2 and water vapor will all behave as ideal gases, and follow PV=nRT. Pressure will increase or decrease to the same extent as the temperature increases or decreases regardless of which gas is in the tire. (Even at 300 psi, which is about 20 atm, there is little deviation from ideality.) Therefore the comments about N2 not changing in pressure as the temperature changes are without merit.

3. The rate of effusion (or diffusion) of a gas through a porous membrane depends on the molar mass and to some degree on the molecular diameter. N2 and O2 are almost the same size and N2 is lighter than O2 (28 g/mol vs 32 g/mol) so if either gas were to effuse out of the tire, nitrogen would do it more quickly. Luckily, tires are designed not to be porous membranes.

4. N2 and O2 both have essentially the same specific heat capacity, about 1.0 J/gK, and thermal conductivity, about 0.00026 W/cmK. Water vapor has a specific heat capacity of about 2 J/gK. But remember, water vapor will constitute less than 1% of the air in the tire. So the idea that N2 has different heat handling properties is also without merit.

5. The ozone, O3, in the atmosphere, which is a ground level pollutant, will do a great deal more damage to your tires than the O2 inside the tire. For instance, don't leave a condom out in the air in Los Angeles for a few days. It will develop lots of tiny holes and weaken.

spdracer22 says that dry air is preferably to air with a lot of water vapor. As a tire heats up, the very small amount of H2O present will be in the vapor state which may contribute to the overall pressure very slightly.

Several have suggested that N2 in a high pressure tank is more portable and requires no electricity. That would make sense, particularly for aircraft tires.

I find no reason to believe that N2 is going to produce a "better ride" or "better handling".

The bottom line is that for general passenger car tires or truck tires there is nothing to be gained (other than portability) by using nitrogen rather than air. The biggest gain will be $$$ by the companies that sell nitrogen handling equipment and the tire merchants that appeal to ignorant customers. And who is the biggest loser? Yep, the consumer."

Skip

[Montana_139]

Skip,

Thank you for the very clear concise information.

Glenn