Which Load Range - Page 2

Tarheel · 04-26-2005, 05:15 AM

The D range marathons carry 51 psi on my 94 34' per Airstream.

jimmickle · 04-26-2005, 07:24 AM

Quote:

Originally Posted by dkekrksk

I am a little unsure about the amount of air I should have in the tires on my travel trailer. I have a 2004, International CCD. On the plaque it has a gross weight of 7300, the size of the tires and the air press should be 65. However, the Good Year manual gives different amounts of air for different weights. Any idea on what the air pressure should be?

Thanks!!

Based on the gross weight, and Goodyear's pressure/load charts, you should be good at 45 psi. My post above (#9) gives pressure/weight carrying capacity. When you get the trailer fully loaded, take it to a scale and get the real weight on the axles and adjust pressure accordingly. Fully loaded, you may be over or under gross weight, so getting real weight on a scale is the only way to be sure.

Jim Mickle

**jcanavera** · 04-26-2005, 09:49 AM

Hmmm...this seems to be the hot topic also on the Yahoo list too. One other thing to consider is that the speed you tow affects tire capacity also. It stands to reason, the faster you go the more the tire flexes and the more heat you generate. Unfortunately most inflation charts don't reflect the speed that those capacities relate to.

The best example relating to this is Airstream's instructions on towing a tandem axle trailer when you have a tire failure. Note they tell you to reduce speed to 45 mph. Why? Well the surviving tire actually has to bear more weight, probably more than its stated capacity. When you slow down, the weight carrying capacity of a tire will actually increase.

Just some food for thought.

Jack

basecamp · 04-26-2005, 10:19 AM

Just another reason to go to the D range. I did have a tire failure, don't know how long I had a flat but when I pulled in for a Big Mac, I walked around the trailer, one tire was flat and was very hot. I changed the tire right there and found out later I picked up a nail on tires that only had about 2000 miles on them. I found out yesterday that Costco in Canada has an option to put Nitrogen in tires instead of air. Nitrogen will keep the air pressure for a much longer time. First time I heard of this.

**Action** · 04-26-2005, 11:17 AM

RV tires are nearly maxed out for load most of the time. (Assume total load of all tires times 80 to 90% being max)

Unlike a SUV or truck that may run 90% of the time empty with little load at all.

>>>>>>>>>>>Action

dmac · 04-26-2005, 01:27 PM

I do not think that pure Nitrogen will leak slower than air, remember that air is 78% Nitrogen anyway.

Nitrogen is used to inflate aircraft struts, where the very high pressure bottles are an advantage. Also Nitrogen has no water vapor (there is a rumor that ice could damage o-rings in aircraft struts). However, I doubt there is any measurable benefit for car or trailer tires.

basecamp · 05-03-2005, 06:57 AM

They use nitrogen in aircraft tires...

Using nitrogen instead of compressed air has distinct advantages, which lead to immediate benefits for the vehicle owner.

1. It has more mass, so it migrates through the tire three to four times slower. The result: Tires hold their psi longer.

2. It runs about 20% cooler. Less heat results in less tire degradation. 3. It drastically reduces oxidation on the rim and inner-liner (nitrogen systems almost totally eliminate oxygen -- the cause of oxidation -- from the mix).

markdoane · 05-03-2005, 08:14 AM

Quote:

Originally Posted by basecamp

They use nitrogen in aircraft tires...

1. It has more mass, so it migrates through the tire three to four times slower. The result: Tires hold their psi longer.

More mass than what? Helium? Most people aren't using helium in their tires.

**Action** · 05-03-2005, 10:01 AM

I believe the air that you are breathing. And the air we use to fill tires has oxygen and nitrogen. Mostly Nitrogen 78% and 21% Oxygen.

However on the period chart (It's a chemical thing) it is less denser than oxygen. So I am not sure about the above statement. So maybe pure oxyen would be a better or more dense thing?! Donn't know. Of course pure O2 is asking for rust.

http://www.lenntech.com/periodic-chart.htm

>>>>>>>>>Action

basecamp · 05-03-2005, 10:50 AM

Come on guys, I'm just trying to help. It says more mass than compressed air(the usual fill). Do some research on the internet, I thought it was interesting to note that the tires run cooler with nitrogen. Yes this is something new to me as well, I'm not making this stuff up as I go along.

markdoane · 05-03-2005, 11:17 AM

Basecamp,

Appreciate the effort, but please check the facts before you post them. Not everything on the internet is correct.

**Action** · 05-03-2005, 11:54 AM

I can see where it would run cooler. Nitrogen is a lighter element. It can not absorbe as much heat. And it would not combine with steel. (Aka rust) However there is not a nitro pump at my local Circle K.

Where does one obtain Nitrogen? Airport? (Sky Harbor in Phoenix is kinda busy.)

>>>>>>>>>>>>>>>Action

basecamp · 05-04-2005, 06:18 AM

Go to Google, type in the search box nitrogen+tires there are quite a few sites that talk about this subject. Some garages are offering the service, Costco. I don't believe everything I read but I believe this... There are alot of posts on the forum that are of someone's opinion, what I stumbled across is fact and hopefully someone will benefit from it. I mentioned this subject to a co-worker, he said that he uses nitrogen in his drag bike for the tires and for an air switch that controls the shifting of his transmission. I'm going to switch to nitrogen. Example site: http://www.airliquide.com/en/medias/...es_filling.pdf

markdoane · 05-04-2005, 06:53 AM

Basecamp,

I'm wasn't disputing your central premise about using nitrogen in your tires. I did say that part of your statement about the mass of nitrogen being heavier, and diffusing 3-4 times slower, is pure bunkum. Other than that un-fact, the rest of your claim is pretty subjective and mostly a matter of personal preference.

There was a previous thread on this forum that discussed nitrogen pretty completely.

I did see one google article that said using nitrogen totally prevents any pressure increase due to tire heating. If that were true, it would be the greatest invention since vulcanized rubber. But it's not true.

Anybody can 'publish' on the WWW, doesn't make it true.