Tire pressure monitors

[micd]

I looked at the internal sensors for sale at Camping World. The person in the shop I talked to said that they were discontinuing them since they broke alot upon installation.

[frankparisi]

Thanks for the info Tireman9. The problem is, at 2psi/ 10* temp rise, setting at 15% should give a good margin. My pressures went above that.
Why, + what is safe?
I sent an e-mail to TST - responded to an e-mail offering extended warranty. I'll let you know when I get a reply or I'll call them on Mon.
Frank

[wingnut60]

I don't think you can get the "safe" psi/temp info from any tire mfg. But can tell you that all QUALITY tires runnning under rated loads at max psi on sidewall will (should) withstand normal pressure/temp buildup. You should not be worried about EXCESSIVE PSI/TEMPS--it is LOW PSI that will build heat and destroy the tire. If you would ever note a really high temp, the tire will have already self-destructed. My TST alarms don't even go off til above 158F--at that temp, BOOM probably already.
If your tire is defective, or of poor manufacture, or something has happened to puncture the tire, then the psi alarm should give you a notice when the pressure is going down. But, sometimes stuff happens to all brands of tires; however, the Chinese seem to delight in having some national effort aimed at destroying the US RV industry with cheap/useless tires.
I towed for 30+ years with no idea of what the pressure in the tires was doing--got the TST and will never, ever, be without some form of monitoring for the trailer.
Joe

[Tireman9]

Originally Posted by edj

How do you know if you are setting the high pressure into the range where the tire is liable to "pop"? I guess the problem is that I do not know how high the pressure can go and still be OK.
I bought a TST system recently, but have not hooked it up yet. Still haven't changed to tire valves to bolt-in metal type.

I can't speak for all tire companies but I think the general design limits would be similar. i.e. Passenger and LTR generally can contain at least 150 PSI with many good for over 200.
It has been a number of years since I designed TB size tires designed for the 100 to 125 psi range but I would again think they can handle pressures in the 200 to 250 range.

All of the above high pressures are achieved on special rims as I do not know of standard rims being capable of the high pressures needed to "pop" a tire.

Tires are designed to be inflated to pressures appropriate for their operating conditions. Design engineers take into consideration normal pressure and temperature increases. i.e. the ambient + 60F range for temperature and cold pressure + about 15 to 20% psi.

NOTE ALL of the above are approximate numbers intended to give you a feeling for the range of temperature and pressures. None of these numbers are absolute. If you never operate a tire overloaded or have a mechanical problem such as alignment, bent axle or wheel, and inflate your tire properly i.e. no excess water I would expect you to see your pressures and temperatures to stay below the numbers above.

If you see increases more than those I have cited then you need to have your rig and tires inspectd.

Hope this general information helps.

[diandtom]

I have a Pressure Pro and had them for five years and only had trouble with one during this time. I need to send them in for new batterys. I would not go anywhere without them.
Tom

[frankparisi]

Tireman 9
Thank you again for the GENERAL information - very good to know + I trust that no one would assume that any specific numbers apply to an individual situation!
I haven't heard from TST - didn't get around to calling them yet.
Frank

[malundquist]

I am interested in the TST system, but I think I read that there is no read-out on the monitor if the rig is standing still. It bothers me that I won't know the pressure readings before I get out on the highway. Does anyone know if this is true about no read-out while standing still.

[TexasPSDX]

Mine reads when parked. In fact last winter I went out and found the low pressure alarm going off. The temperature had dropped fairly low overnight, causing the tire pressure to read low. As soon as the sun came out and things warmed up a little alarm reset. I have the 10 tire system, 4 on the truck and 6 on trailer (3 axle). Glad to have it.

[frankparisi]

It has switch. In one position it goes to sleep after being stopped for a while.
I flip the switch when I'm starting to break down camp or bring it in + watch it while having coffee. It takes a few minutes to start reading.

[Tireman9]

Originally Posted by Dutch & Diana Irrgang

We had a brand last year that just didn't work for us. 2 months ago we decided to try again and we were super impressed with the TST TPMS system. I saved us within 380 miles by letting us know a 5 year old valve stem had failed and we were losing air in that tire.
A good product at a reasonable price. Diana

I know this is an old post but am wondering if you remember which part "failed".
Was it the metal stem or the rubber gasket that seals the metal stem to the metal wheel or the valve core that screws into the metal stem?

[Tireman9]

Originally Posted by TexasPSDX

Mine reads when parked. In fact last winter I went out and found the low pressure alarm going off. The temperature had dropped fairly low overnight, causing the tire pressure to read low. As soon as the sun came out and things warmed up a little alarm reset. I have the 10 tire system, 4 on the truck and 6 on trailer (3 axle). Glad to have it.

Given the rule of thumb of 2% pressure drop for each 10°F drop I wonder how cold it got or how close to the low pressure warning setting you are running.
If your inflation pressure is 100 psi and the tep dropped 50°F, I would expect to see about 8 to 10 psi drop. If you are running the suggested 10 psi over the minimum recommended infl and have a 20% low warning then something doesn't seem to add up. I am only guessing here so am just wondering what the real numbers are.

[Dutch & Diana Irrgang]

I should have been more clear. It was a rubber valve stem and the tire was 5 years old. We were just waiting to get someplace to have metal valve stems put on when the alarm sounded. We had the metal valve stems put in at the next town we came to. Diana

Originally Posted by Tireman9

I know this is an old post but am wondering if you remember which part "failed".
Was it the metal stem or the rubber gasket that seals the metal stem to the metal wheel or the valve core that screws into the metal stem?

[Tireman9]

Giane & Dutch
FYI standard rubber "snap-in" valve stems of the 400 series like on left in picture



(number is molded in the base of valve) are rated Max 65 psi cold. There are few RVs of any size that need less than that and I see no reason to try and save $5 to $10 per vehicle given the potential for failure at high pressure. Also remember the rubber parts of any valve should be replaced whenever you replace tires ( 5 to 8 years).

[Dutch & Diana Irrgang]

Thanks I guess? I'm not sure why you directed your reply to me as we stated our tires had rubber stems and were 5 years old. We had planned to have the stems replaced with metal stems but received our TST before we had that done. Hence, the alarm went off-showing that it was working-but it worked because the stem was too old to support the sensor. Diana

Originally Posted by Tireman9

Giane & Dutch
FYI standard rubber "snap-in" valve stems of the 400 series like on left in picture



(number is molded in the base of valve) are rated Max 65 psi cold. There are few RVs of any size that need less than that and I see no reason to try and save $5 to $10 per vehicle given the potential for failure at high pressure. Also remember the rubber parts of any valve should be replaced whenever you replace tires ( 5 to 8 years).