So I made an amazing discovery today. I got my new Sailuns partially installed today (so far). When I took the old tires and rims to Discount Tire, they were easy to lift and move into my truck. When I picked up the new Sailuns they were really heavy. Same rims. The old had nitrogen and the new has plain old air. So it must be the air.Sure it has nothing to do with going from an F rated tire to a G rated. :B

Be sure to check the pressure in the new tires. When I had DT mount my new tires they said they could only put 80psi in the tires because of their euip.Good thing I asked.

Atom for Atom, Nitrogen is Lighter than AirNitrogen has an Atomic Weight just over 14 & Oxygen has an Atomic Weight of almost 16Air,,,,mixture of Oxygen & Nitrogen will be 'heavier' then NitrogenAir,,,,78%-Nitrogen, 21%-Oxygen, 1%-Argon, water vapor/trace elementsSo your hypothesis is correct......air filled tires are heavier then nitrogen fill onesCourse size/heft of an 'F' rated tire VS size/heft of a 'G' rated tire throws a monkey wrench in the whole conceptLOL......

Here is one example of the massive loss of weight:The weight difference between oxygen and nitrogen is less than 3%, but let’s take the full 3%.One 255/40/17 summer tire holds approximately 13.88 liters (0.5 cu.ft.) of air at 2 bar (29.4 psi).One liter of air is roughly equal to 1 gram so there are roughly 13.88 grams of air per tire, 55.52 grams in all 4 tires. Nitrogen is 3% lighter than oxygen, but there’s only 22% oxygen in air, so the difference in weight from all 4 tires is 0.3664 grams, that’s a whopping one third of a gram!Here’s the math: 55.52 gr x 0.03 x 0.22 = 0.3664 grTo put it in perspective, one official ping pong ball weighs 2.7 grams.

Reminds me of a funny story I heard once from a factory maintenance foreman I knew. He told a young apprentice once to get dolly because they needed to bring a small portable air tank to a location and the tank had 150 pounds of air inside. Apprentice fell for it and got the dolly.:SDan

Hammerboy wrote:Reminds me of a funny story I heard once from a factory maintenance foreman I knew. He told a young apprentice once to get dolly because they needed to bring a small portable air tank to a location and the tank had 150 pounds of air inside. Apprentice fell for it and got the dolly.:SDanWonder what the kid would have done if it was a scuba tank with 2,500 psi?

Weight of air vs. Nitrogen | Good Sam Community

Campinfan
Explorer III
Aug 31, 2020
So If I fill the tires with helium, which would lift the trailer a bit due to helium being lighter than air, can I tow my 41 foot 5ver with a half ton? I could sell my F350 and get something a bit less expensive like an F 150.
aruba5er
Explorer
Aug 30, 2020
are you sure they didn't fill tires with HELIUM?
C_Schomer
Explorer
Aug 30, 2020
I used to do a lot of med gas line brazing while purging with N. If I didn't have enough N flow on the bigger lines the N and air would stratify and come out N on top and air on the bottom. Craig
cummins2014
Explorer
Aug 29, 2020
Hammerboy wrote:
Reminds me of a funny story I heard once from a factory maintenance foreman I knew. He told a young apprentice once to get dolly because they needed to bring a small portable air tank to a location and the tank had 150 pounds of air inside. Apprentice fell for it and got the dolly.:S

Dan

We used to send the new guys to look for a metric crescent wrench . :)
agesilaus
Explorer III
Aug 29, 2020
I guess you have to be a real He-Man to do SCUBA then, since those tanks hold 3000 pounds of air
TXiceman
Explorer II
Aug 29, 2020
Yep, going from 80 to 100 is 20 pounds extra on each tire. If you go 110, then that will be 30 pounds extra per tire.

Also, it makes a huge difference if they used winter air instead of summer air.

Ha ha ha,

Ken
MitchF150
Explorer III
Aug 28, 2020
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Campinfan
Explorer III
Aug 28, 2020
I may try it at 105. I do need to get it to the scales just to verify the weight. In 20 years of camping I just had my first blow out. I was a crash investigator in my previous life so I am pretty fanatical about the tires. We travel pretty light, no water on board (just a few adult beverages), and I don't tend to gather lots of stuff so that is good.
Old-Biscuit
Explorer III
Aug 28, 2020
Campinfan wrote:
I love the responses here. The manager who took care of me was a fellow RVer. He told me they would air them up to 110 lbs since that is what the sidewall says. I really need 95 but I may keep them at 110 or maybe a little less. Time will tell. I always check the air in my tires (truck and trailer) when we are getting ready to use the trailer.

All 4 tires are now on my rig. Of course, I had to pick the day of thunderstorms to do it.

Lynnmor---math makes my head hurt so I will just take it as gospel about what you wrote...lol.

My 5th wheel has a GVWR of 14,400#....scaled weight when FULL TIMING was 13,873#.
'G' Rated tires 110# MAX PSI on sidewall ...... I ran 100# and got good EVEN wear across the tread.

Your 5vr has a GVWR of 15,500#
Scale it for 'camp ready' weight and adjust tire pressures accordingly so you are NOT 'overinflated' (center wearing/harsher ride) or 'underinflated' (wear on inner/outer & increased chances of BLOWOUTS due to Heat Build Up!!)
Campinfan
Explorer III
Aug 28, 2020
wow I never realized I was that strong....thanks RobWNY