How much pressure increase can the G614's stand?

[drjjj]

Put upgraded wheels (to accommodate G614's) and five new G614's on our 2007 3400RL last year. Upgraded our TPMS from Pressure Pro to TST because I really like the temperature and pressure readout instead of just pressure. Went to northern NM last fall-uneventful trip. Now in NM/AZ/NV and the pressure in the morning when leaving the campsite is 106-108 in all five tires. The installing dealer set the TST system. By late morning the pressure in the tires on the ground is hitting 128-132 and setting off the alarm. The temperature is staying around 77-85 depending on where the sun is on the tires. Is the alarm set too low? How much increase in pressure can these tires stand?

[Ram Montana High Country]

If nothing else, this points out a potential good reason to put nitrogen in the tires to have less pressure increase from temperature.

Thank you for asking a good questions

[dieselguy]

He already has 78% nitrogen in his tires ...

[GLS3950]

I don't ave my manual here but I believe the default setting is 157. You can check your manual it should tell you how to go back to default settings.

[DQDick]

TST's manual says 20% above and 10% below what you run the tires at is typical for where to set the sensors.

[rohrmann]

The TST manual has information that says the following are the factory presets of the monitor, and as we run our G614's at 105 to 110 psi, all the presets were just fine. Our tires regularly go above 135 psi when in hot conditions, and usually the tires on the sunny side are at least 10 degrees higher than the shady side. We have had no issues with any pressure increase when towing.

The default factory presets are:
a. High Pressure Alert: 175PSI (12.1 BAR)
b. Low Pressure Alert: 100PSI (6.9 BAR)
c. High Temperature Alert: 70'C (158'F)

[scottz]

Originally Posted by rohrmann

The TST manual has information that says the following are the factory presets of the monitor, and as we run our G614's at 105 to 110 psi, all the presets were just fine. Our tires regularly go above 135 psi when in hot conditions, and usually the tires on the sunny side are at least 10 degrees higher than the shady side. We have had no issues with any pressure increase when towing.

The default factory presets are:
a. High Pressure Alert: 175PSI (12.1 BAR)
b. Low Pressure Alert: 100PSI (6.9 BAR)
c. High Temperature Alert: 70'C (158'F)

Same with my TST system. I also see pressure that high with the sunny side higher.

I set my COLD tire pressures to 110 and don't worry about the increase. The tires are engineered to accept the increase in temp/pressure.

[coachgrowl]

I set my pressure to 100 and see similar increase.

[Ram Montana High Country]

here's alink and some information on running higher nitrogen content for me. The information on moisture helps explain to me the higher increase of pressure in tires.

With my racing pit crew background, the air migration was my first reason for adding nitrogen to tires.

https://www.popularmechanics.com/car...a3894/4302788/

First is that nitrogen is less likely to migrate through tire rubber than is oxygen, which means that your tire pressures will remain more stable over the long term. Racers figured out pretty quickly that tires filled with nitrogen rather than air also exhibit less pressure change with temperature swings. That means more consistent inflation pressures during a race as the tires heat up. And when you're tweaking a race car's handling with half-psi changes, that's important.
Passenger cars can also benefit from the more stable pressures. But there's more: Humidity (water) is a Bad Thing to have inside a tire. Water, present as a vapor or even as a liquid in a tire, causes more of a pressure change with temperature swings than dry air does. It also promotes corrosion of the steel or aluminum rim.
If I ever need to top off a tire when I'm out on the road, I'll always briefly depress the tire chuck's valve with my thumbnail and vent some air. If my thumb gets wet, there's water in the line. Some gas stations don't do a very good job of keeping the humidity out of their air system. I don't even like to use a water-based tire-mounting lubricant unless I can let the tire bake in the sun for a couple of hours before I air it up and seat the bead. I've dismounted tires (not mine) that had several quarts of water inside—probably from a compressed-air hose that collected water and was never purged properly.

[scottz]

Sounds like it might be beneficial, but everyone has to do their own cost-benefit analysis. I have a friend that owns two tire stores. I asked him about the benefits of nitrogen; he said the biggest benefit was that he gets to charge $10 per tire for it. I might consider it, but only if I could get my own tank.

[CaptnJohn]

Originally Posted by scottz

Sounds like it might be beneficial, but everyone has to do their own cost-benefit analysis. I have a friend that owns two tire stores. I asked him about the benefits of nitrogen; he said the biggest benefit was that he gets to charge $10 per tire for it. I might consider it, but only if I could get my own tank.

My tire dealer says the same thing. He does not offer it but has it available if asked.

[mlh]

I like 78% nitrogen. I think that’s the best cost benefit ration.
Lynwood

[scottz]

Originally Posted by mlh

I like 78% nitrogen. I think that’s the best cost benefit ration.
Lynwood

It's worked for a long time.

[mhs4771]

I was advised: If you can get it for FREE it's worth it
but if you have to pay for it, it's not worth it.
Plus in order to change out the air already in a tire and refill with nitrogen is a special process to purge all the current air out and refill with pure nitrogen, much more than just releasing the air and then filling with nitrogen.

[beeje]

Nitrogen, complete waste of time and $$ IMHO. What are you going to do if your TPMS says a tire is low on air. I sure you do not have a way to add nitrogen on the road. If you add air you will have to remove all air/nitrogen and return to all nitrogen at some point.

As far as the increase in air pressure while driving down the road, all tires air pressure increases with ambient air temp/sunlight on tires/speed etc. All tires are designed to handle the increase.

I have seen around 130 psi from the TST 507 on my trailer tires on the sunny side.

[CaptnJohn]

Originally Posted by beeje

Nitrogen, complete waste of time and $$ IMHO. What are you going to do if your TPMS says a tire is low on air. I sure you do not have a way to add nitrogen on the road. If you add air you will have to remove all air/nitrogen and return to all nitrogen at some point.

As far as the increase in air pressure while driving down the road, all tires air pressure increases with ambient air temp/sunlight on tires/speed etc. All tires are designed to handle the increase.

I have seen around 130 psi from the TST 507 on my trailer tires on the sunny side.

Agree 100%

[masterdrago]

Originally Posted by rohrmann

The TST manual has information that says the following are the factory presets of the monitor, and as we run our G614's at 105 to 110 psi, all the presets were just fine. Our tires regularly go above 135 psi when in hot conditions, and usually the tires on the sunny side are at least 10 degrees higher than the shady side. We have had no issues with any pressure increase when towing.

The default factory presets are:
a. High Pressure Alert: 175PSI (12.1 BAR)
b. Low Pressure Alert: 100PSI (6.9 BAR)
c. High Temperature Alert: 70'C (158'F)

Bob, I pretty much run the same setup as you. Do you have a low alert go off when it is really cold. Mine drops below 100psi and I have to kill it on the 507.

Also, for the nitrogen fans, don't you have to completely evacuate all the air from the tire b4 filling with nitrogen. I have it at home for other uses but did not think it was a good idea to pull a vacuum on my tires!

[beeje]

When I installed the TST 507 I set the camper tires at 110# with an alarm of low pressure at 99. I set the trucks tire at 70 with a low alarm at 60. This was in 75 degree temps when set. We took off for a trip thanksgiving week end, and a few minutes after I started the truck I had multiple alarms on almost all the tires. I just unplugged it until we drove a bit to warm to tires up.

Cold weather really lowers the air pressure. Way more that a thought

[phillyg]

Mfgrs. already take daily temps into consideration. Unless you're in Antarctica or the hottest desert in the world, you're supposed to fill your tires to the mfgrs. specs in the morning.

[beeje]

What I am saying is the tires were aired up to 70 when the ambient temp was 75. No air was lost from the tires do a leak. Now, say 2 months later its 20 degrees and the air pressure is gauged at 60. Am I wrong to think one should not air them back up to 70. If the air temp was to return to near 75 the next day, the tire pressure would go up towards what it was when first aired up.