Tire pressure monitoring system dumb questions

[BillHoughton]

Looking at a tire pressure monitoring system for my 2007 Sprinter-based RV. Folks have recommended TST and TireMinder, and I'm looking into those. I have a couple of really dumb questions:

1. The sensors that take the place of valve caps seem to come in two flavors: just plain caps that you remove when you're airing up, and flow-through caps that you can leave in place when adding air. I'd be using the plain ones on the front (smaller and thus less likely to get damaged) and the outer rear (likely could not get an air chuck in there with a cap on) tires, but the idea of sensors/caps that I can leave in place on the inner rears is attractive, since the vent holes in the Sprinter wheels are small and my hands are not small. Do I need to be concerned about leakage from flow-through sensors?

2. Both the companies I noted above use battery-powered sensors (CR1632 batteries in both cases). How long do these batteries last in use? I would, of course, carry spares. There references to systems that use RFID sensors, not requiring a battery; don't know if there are good systems that use them.

3. How do you teach the monitor which sensor is on which wheel? I was looking at the TST manual online, and it appears to say that, when you set it up, it can tell which sensor is on which tire. Is that right?

4. Does anyone here put a sensor on the spare tire? The current spare tire cover is a bear to remove, although it's failing and I'm replacing it anyway; but the less time I have to spend fussing around before trips, the better!

[Dusty_R]

I keep it simple, I use a hand held radiant thermometer, and check tire temperature at rest stops. I also carry an air compressor.

Dusty

[RambleOnNW]

I have used TST TPMS products for a number of years on our E450 'C' and am satisfied with their performance. Currently using both flow-through and regular 507 products. Battery life is around 1.5-2 years.

The flow-throughs are on the rear duals placed upon Borg solid metal stems so both TPMS sensors are easily accessible from the outer tire side. The regular TPMS sensors are on the front attached directly to the stems on the wheels and fit within the openings in the wheel simulators.

No air leaks on either type of TPMS, have not added air to the fronts for more than 1 year. Started out with about 62psi and have about 60psi currently.

I change the pressure on the rear regularly depending on the outside temperature where we are. I like to have about 78psi cold and 88 psi hot.

The way I program the sensors is that they have small labels from 1-6 that you place on the sensors to track position. Then take the base unit inside with 1 sensor at a time away from the other sensors (so they don't interfere) and the set-up will allow you to associate the sensor with a wheel position.

I don't put a sensor on the spare tire as I carry a tire compressor at all times so would just use that to inflate the spare if needed.

I carry a couple of spare TST sensors just in case. If there is a battery failure I will just swap sensors on the road. Had one flow-through not flow very well which I replaced out of warranty.

[STBRetired]

have the TireMinder A1A system with 10 transmitters and am very pleased with it. Comes with repeater so no issues with lost signal from towed. Minder has free battery replacement, so I change them every year. Have never had one go dead. I do not have flow through sensors. Went with the cap replacement ones as they do not stick out as far. In 4 years have lost one sensor to a road hazard. Was smashed but there were no marks on rim or vehicle so all I could think of was it caught a rock. Did not leak any air, but quit transmitting. One of the people we travel with has TST 507 system and they are happy with it, so I would say you could go either way and be fine.

[garmp]

Bill, thanks for the post. I to am in the market for a TPMS and looking at the ST-507-FT-6 Flow Through, but know nothing about them as far as the pro's and con's are other than these units have high ratings.
I have zero mechanical abilities and want a system that is dependable, easy to maintain and simple to use. Good responses to the post. Thank you all.

[youracman]

Just a data point for ya Bill.

The PO of my coach had installed the TST system and it came with the coach when I bought it. I like it fine......been in use about 6 years now. Flow thru sensors are on the duals and the only rub is that it took forever (or a little longer) to top them off thru those flow thrus using my old (nice and light) 100 psi pancake compressor. So I gave the little pancake to my grandson for bike tire air ups, etc and bought a 150 psi pancake compressor. The 150 psi unit performs very well (amazing difference, actually) .....just a little more weight though to count against my already "tight" GVWR.

Talked to the owner there at TST and he was not surprised. He said "You wouldn't believe how small that little air-up hole is inside the flow thrus." I'd buy the TST system if I were in the mkt, but there are others just as good, I believe.

Safe travels................. ed s

[RCMAN46]

When was the last time you checked the tire pressure of your spare tires?

One time that I did I found the pressure at 45 psi on a 80 psi tire.

That spare would not have been able to handle the load on a rear tire of my truck should it have been needed.

That is when I included sensors on my spare tires.

[RoyF]

1. Leakage is likely unless you use steel valve stems. When a rubber stem developes a leak, the tire must be dismounted in order to replace the stem.
2. My TST batteries usually last a couple of years. They are easy to replace.
3. Each sensors is "married" to a particular tire when you first set up the system. That's something you do only once.
4. Speaking for myself, I don't have a sensor on the spare.

[MobileBasset]

I have had the Tire Minder system for 5 years. I have 6 removable cap sensors on brass valve extenders. It was at least a year before I had to change any cap battery. Replacing batteries in the caps is very easy. After about 2 or 3 years one of the cap cases cracked so I had to replace it. I bought the very inexpensive cap kit with multiple cases and O rings. After four years one of the sensors locked up at a constant reading. I replaced it. The receiver/computer has a learning mode to set up which caps are on which tire. The system has been very useful and reliable, has calibrated well against a high accuracy manual gauge, and requires no fussing. I read the receiver whenever I want and leave it on continuously when I am traveling to alert me when issues arise. The receiver is always plugged into power when I am driving. So far the receiver battery is going strong. The receiver battery is not replaceable.

I don’t use a sensor on the spare. I can add air when it gets installed and will use the bad tire sensor.