Tire pressure monitor?

[Mndiver]

Newbie here, we just bought a used 2017 keystone sprinter 26rb. Am thinking I should have a tire pressure monitor. What a bewildering array of choices. anyone using one they are happy with. Need it for trailer only, TV is a 2020 tundra so has its own. thanks. steve

[sourdough]

Welcome to the forum. I and many others use the TST 507 system and highly recommend it.

[flybouy]

Welcome to the forum.

I also use the TST 507 and love it. You do have to be cognizant of where you place the monitor as the screen can be difficult to read in direct sunlight. I would suggest also a good weight distributing hitch with 4 point sway control built in with that much trailer. At nearly 30' with a GVW of 9,00 lbs the hitch weight will be over 1,000 lbs.

[travelin texans]

X3 on the TST507.

[jasin1]

If you can’t find the tst brand or they are out of stock …I have the eeze brand tpms and I’ve been very happy with it. Very similar…I have the monochrome version and it’s rechargeable and pretty easy to see…I think the color versions are harder to see

[Roper46]

Welcome from south Georgia. I use the TireMinder TPMS and love it.

[Northofu1]

I have the tire minder it works very well, so far. It was also cheaper than the TST on amazon.

[wiredgeorge]

Since many of the TPMS systems that are a favorite may be out of stock due to them being made in the Far East and the pandemic, I couldn't find any of the more popular when I got one for Christmas gift so told the gifter to get a Guta system from Amazon due to good reviews. The instructions are incomprehensible to this older person and I had to call their tech support for help setting it up. The tech support was GREAT and they walked me through it. So far the Guta TPMS works properly.

[sourdough]

I am not aware of a shortage on the TST systems. Just checked Amazon for the TST 507 system with 4 sensors and they are in stock @ $368.

[wiredgeorge]

Originally Posted by sourdough

I am not aware of a shortage on the TST systems. Just checked Amazon for the TST 507 system with 4 sensors and they are in stock @ $368.

Not sure you were checking last late October or early November when my kiddo bought me one. There was a shortage there. Do you think I am lying about it? Just wanted to point out what I bought and am using.

[sourdough]

Originally Posted by wiredgeorge

Not sure you were checking last late October or early November when my kiddo bought me one. There was a shortage there. Do you think I am lying about it? Just wanted to point out what I bought and am using.

Whoa there George! I had nothing to say about what you bought or when you bought it or what things were like a year ago - I have zero idea of what you encountered then, didn't reference it at all and don't care. I know there have been shortages of various things - these guys are in San Antonio as I recall. Hadn't seen any mention of shortages from them since I DO buy things from them (rebuild kits, spare sensors, batteries etc.) from time to time.

You mentioned that "many of the TPMS systems that are a favorite" could be out of stock due to shortages. I simply wanted to clarify that single statement in your post as it related to TST systems at this time.

[travelin texans]

Whatever system you chose I'd recommend a couple things;
#1 it gives pressure & temperature readings
#2 batteries are user changeable
#3 my opinion is that it must have its own monitor that displays temps/pressures constantly, not using your cell phone.
#4 be sure to have metal valve stems installed on all the wheels.

[RickV]

Originally Posted by travelin texans

Whatever system you chose I'd recommend a couple things;
#1 it gives pressure & temperature readings
#2 batteries are user changeable
#3 my opinion is that it must have its own monitor that displays temps/pressures constantly, not using your cell phone.
#4 be sure to have metal valve stems installed on all the wheels.

Agree with all of this, pay special attention to number 4 (speaking from experience). I use Tiretraker TPMS I have the old model 400 monitor thinking about upgrading to their model 600, same sensors just better readout.

[FlyingAroundRV]

Originally Posted by travelin texans

Whatever system you chose I'd recommend a couple things;
#1 it gives pressure & temperature readings
#2 batteries are user changeable
#3 my opinion is that it must have its own monitor that displays temps/pressures constantly, not using your cell phone.
#4 be sure to have metal valve stems installed on all the wheels.

I'll second all that except the metal valve stems. They are good IF you can fit them to your rims. My rims won't take them but I've been running with standard stems for two seasons and over 20,000 miles with no problems … yet
PS, I have the TST 507 with flow thru sensors.

[wegone]

I just purchase the TST 507 system with 4 sensors yesterday....

If you go directly to the store that sells them through Amazon, and get a 10% discount on your first order, and no sales tax, you save 70 bucks.

https://awegoo.com/

Just type in TST 507 on their search menu.

[Camp CA]

I installed a Tiretracker TT-600 to monitor my 10 tires.........6 on tow vehicle and 4 on the trailer. Nice display.

[jadatis]

Also keep in mind, that TMPS also introduces new things to worry about. Then if you learn, what is important, and what not, you yudge the readings better.

1. Temperature reading of external sensors isworthless, because it gives the temperature of the end of the valve, and not the gascompound in the tire ( fi air or Nitrogen).
And even internal sensors dont always give temp of inside tire gascompound, metal valves transport the temp of rimm and outside tire air to the sensor.

But you can calculate the pressure back from the pressure, rising.

For that I made a list.
Gives pressure filled at 70 degrF, and the temperature rising ( or lowering) per psi.
So look up the pressure you fill cold at 70 degrF back in this list, and remember or write down the degrF/psi behind it.

Then on the road if you see 5 psi pressure rising on tmps , multiply by the degrF/ psi, and add that to 70 degrF, and you know more exact the temperature of the inside tire .

Never 100% exact, but better then what sensor gives. And because of all the inacuracies also never exact. So you can do rough calculation by head while driving, acurate enaugh for the purpose.

Pressure measured at 70 degrF/ degrF per psi.

70degrF./degrF/psi

20 psi/ 15,5F/psi
21 psi/ 15F/psi
22 psi/ 14,5F/psi
23 psi/ 14 F/psi
24 psi/ 13,5F/psi
25 psi/ 13,5F/psi
26 psi/ 13 F/psi
27 psi/ 12,5 F/psi
28 psi/ 12,5 F/psi
29 psi/ 12 F/psi
30 psi/ 12 F/psi
31 psi/ 11,5 F/psi
32 psi/ 11,5 F/psi
33 psi/ 11 F/psi
34 psi/ 11 F/psi
35 psi/ 10,5 F/psi
36 psi/ 10,5 F/psi
37 psi/ 10 F/psi
39 psi/ 10 F/ps
40 psi/ 9,5 F/psi
42 psi/ 9,5 F/psi
43 psi/ 9 F/psi
45 psi/ 9 F/psi
46 psi/ 8,5 F/psi
49 psi/ 8,5 F/psi
50 psi/ 8 F/psi
53 psi/ 8 F/psi
54 psi/ 7,5 F/psi
58 psi/ 7,5 F/psi
59 psi/ 7 F/psi
63 psi/ 7 F/psi
64 psi/ 6,5 F/psi
70 psi/ 6,5 F/psi
71 psi/ 6 F/psi
77 psi/ 6 F/psi
78 psi/ 5,5 F/psi
86 psi/ 5,5 F/psi
87 psi/ 5 F/psi
96 psi/ 5 F/psi
97 psi/ 4,5 F/psi
109 psi/ 4,5 F/psi
110 psi/ 4 F/psi
126 psi/ 4 F/psi
127 psi/ 3,5 F/psi
148 psi/ 3,5 F/psi
149 psi/ 3 F/psi
177 psi/ 3 F/ps

[mudrockatc]

TST 507 all the way!!

[jasin1]

Originally Posted by jadatis

Also keep in mind, that TMPS also introduces new things to worry about. Then if you learn, what is important, and what not, you yudge the readings better.

1. Temperature reading of external sensors isworthless, because it gives the temperature of the end of the valve, and not the gascompound in the tire ( fi air or Nitrogen).
And even internal sensors dont always give temp of inside tire gascompound, metal valves transport the temp of rimm and outside tire air to the sensor.

But you can calculate the pressure back from the pressure, rising.

For that I made a list.
Gives pressure filled at 70 degrF, and the temperature rising ( or lowering) per psi.
So look up the pressure you fill cold at 70 degrF back in this list, and remember or write down the degrF/psi behind it.

Then on the road if you see 5 psi pressure rising on tmps , multiply by the degrF/ psi, and add that to 70 degrF, and you know more exact the temperature of the inside tire .

Never 100% exact, but better then what sensor gives. And because of all the inacuracies also never exact. So you can do rough calculation by head while driving, acurate enaugh for the purpose.

Pressure measured at 70 degrF/ degrF per psi.

70degrF./degrF/psi

20 psi/ 15,5F/psi
21 psi/ 15F/psi
22 psi/ 14,5F/psi
23 psi/ 14 F/psi
24 psi/ 13,5F/psi
25 psi/ 13,5F/psi
26 psi/ 13 F/psi
27 psi/ 12,5 F/psi
28 psi/ 12,5 F/psi
29 psi/ 12 F/psi
30 psi/ 12 F/psi
31 psi/ 11,5 F/psi
32 psi/ 11,5 F/psi
33 psi/ 11 F/psi
34 psi/ 11 F/psi
35 psi/ 10,5 F/psi
36 psi/ 10,5 F/psi
37 psi/ 10 F/psi
39 psi/ 10 F/ps
40 psi/ 9,5 F/psi
42 psi/ 9,5 F/psi
43 psi/ 9 F/psi
45 psi/ 9 F/psi
46 psi/ 8,5 F/psi
49 psi/ 8,5 F/psi
50 psi/ 8 F/psi
53 psi/ 8 F/psi
54 psi/ 7,5 F/psi
58 psi/ 7,5 F/psi
59 psi/ 7 F/psi
63 psi/ 7 F/psi
64 psi/ 6,5 F/psi
70 psi/ 6,5 F/psi
71 psi/ 6 F/psi
77 psi/ 6 F/psi
78 psi/ 5,5 F/psi
86 psi/ 5,5 F/psi
87 psi/ 5 F/psi
96 psi/ 5 F/psi
97 psi/ 4,5 F/psi
109 psi/ 4,5 F/psi
110 psi/ 4 F/psi
126 psi/ 4 F/psi
127 psi/ 3,5 F/psi
148 psi/ 3,5 F/psi
149 psi/ 3 F/psi
177 psi/ 3 F/ps

Huh??……that’s a lot of numbers
.
.refrigeration uses a pressure temp relationship because a particular gas has a specific pressure at a specific temperature…you can figure out what kind of refrigerant is in a system based on that( as long as it isn’t multiple types thrown in.

But I believe the tpms on the valve stems use an internal temp sensor that measures the inside wheel air temp itself….I have multiple different hvac instruments that do that ..or it converts it in its reading displayed

This is from my faq questions for my tpms monitor..it states the temp is from within the tire not external

[Tireman9]

Originally Posted by jasin1

Huh??……that’s a lot of numbers
.
.refrigeration uses a pressure temp relationship because a particular gas has a specific pressure at a specific temperature…you can figure out what kind of refrigerant is in a system based on that( as long as it isn’t multiple types thrown in.

But I believe the tpms on the valve stems use an internal temp sensor that measures the inside wheel air temp itself….I have multiple different hvac instruments that do that ..or it converts it in its reading displayed

This is from my faq questions for my tpms monitor..it states the temp is from within the tire not external

Not sure if I agree that an external TPMS is reporting the temp of the air inside the tire.

1. Air is a good insulator so why / how would that small column of air inside the stem override the temperature of the Brass stem that is conducting heat directly from the rim to the metal base of the sensor?

2. My test of running both an internal and external sensor shows the external sensors run 20F to 30F cooler than the internal sensors
3 Tire pressure with change by about 2% for each change in temperature of 10°F. I posted the mathematical proof on my blog.