Tire pressure monitoring systems

[Knightab]

Originally Posted by docj

I already called and spoke with Mike at TST and I asked that exact question. The answer was "no" there is no way to turn off the MH tires and just have the toad's active.

Bummer!

[docj]

Originally Posted by Knightab

Bummer!

IMO my CR-V's OEM TPMS system is so bad that I don't mind spending $59 for a new monitor if that results in my having one that actually works. There is nothing worse than a safety system so bad and so prone to false alarms that the first thing you do when you see the alarm light is to assume it is a false alarm and reset it. That means that if it is actually signaling a low tire I would have to get a second alert before I would pay any attention to it.

[Woofer-01]

Originally Posted by ShapeShifter

...After a fuel stop and a total of 87 miles since the topoff, with the tire pressure still at the topped off pressure, I hear a bang, the TPMS immediately starts beeping, and the tire reads 0 PSI. I immediately pull over, the attached picture shows the result. This is the inside driver side dual, the blowout is on the side facing the outer tire.

I'm asking this first... what is the manufacter recommended pressure for the rear tires? Next the tire manufacturer - What is the max pressure for this tire?
Then conjecure on my part...
Any chance you had a rock wedged between the dual'lys?

[jerichorick]

Originally Posted by docj

IMO my CR-V's OEM TPMS system is so bad that I don't mind spending $59 for a new monitor if that results in my having one that actually works. There is nothing worse than a safety system so bad and so prone to false alarms that the first thing you do when you see the alarm light is to assume it is a false alarm and reset it. That means that if it is actually signaling a low tire I would have to get a second alert before I would pay any attention to it.

docj, consider this. What did you do before TPMS were required on cars? Yes, the CR-V TPMS is not great but it is of some value. It forces us to check our tires more often than when we didn't have the system. Mine triggered the other day. I stopped and examined the tires. I didn't have a gauge with me, but that would have been good to use. All looked good so I reset the alarm (so I would not go into D3 mode) and continued my drive. The next morning I checked my tires and found one down a couple of pounds. Now I'll keep a better eye on them to make certain I don't have a slow leak. As tireman stated above, early warning is better than no warning at all.

Happy trails,
Rick Y

[ShapeShifter]

First off, a correction: in my last post I said they were Michelin XZA2 tires, they are in fact XZA3.

Originally Posted by Woofer-01

I'm asking this first... what is the manufacter recommended pressure for the rear tires? Next the tire manufacturer - What is the max pressure for this tire?

Michelin's minimum pressure for maximum rated load is 110 PSI. Based on an actual weighing, my actual rear tire load is less, which according to Michelin's inflation charts says I need at least 90 PSI. I was running them at 100 PSI.

Then conjecure on my part...
Any chance you had a rock wedged between the dual'lys?

I suppose anything is possible.

[ShapeShifter]

Originally Posted by jerichorick

As tireman stated above, early warning is better than no warning at all.

Precisely! And if he already has better sensors on his toad that can report the actual pressure, why not add a second monitor since they are so cheap?

With my TPMS system, when it came time to replace the sensors due to failing batteries, it was almost as expensive as buying a complete system. So that's what I did, and now having a second monitor, I put that in my toad with it programmed to only show the toad's tires. That worked well when my toad didn't have a factory TPMS. Now, with my new toad that includes a factory TPMS, it's still useful because with all of the information that I can bring up on the dash display (including front/back and side/side vehicle tilt angles and steering wheel turn angle!) it can't display the actual tire pressures!

Yes, there is always visual inspection and walking from tire to tire with a gauge, and that's something that we should all do from time to time. But if you got the proper sensors already in place, why not add the ability to use that information?

[flaggship1]

Originally Posted by PushedAround

Didn't feel like reading through everything, so sorry if this was mentioned but one thing that I like about my TST 507 system is that the display will run on a full charge for at least 50 hours. I just used mine for 2,500 miles and it still shows an almost full charge. Nice to have one less cord flopping around.

X2. It's a great system.

[Tireman9]

Originally Posted by ShapeShifter

You know, you got me thinking. I had a blowout a couple years ago, and I've been trying to figure out what went wrong. I wonder if a lack of this early warning was a contributing factor. This statement, and some of your blog posts that I read recently, has me thinking.

First, I run my rear tires at 100 PSI, my weight calculations say they should be at 90 PSI. My TPMS is programmed to give the first stage low pressure alert at 90 PSI. There is no slow leak warning, only a fast leak which is defined as 2.8 PSI loss in less than 12 seconds (a fast leak indeed!) The tires at that time were 6 year old Michelin XZA2 275/80R22.5 with 40,000 miles on them.

So, I started out a trip with topped off tires, the rears being at 100 PSI. After driving just over 90 miles, my TPMS starts beeping, I have a rear tire that is below 90 PSI (I don't remember the exact number, it was somewhere in the high 80s. I'm coming up on an exit, so I immediately get off the Interstate (within a mile or two) and stop on a side road. A physical check of the tire shows no obvious damage, leak, or puncture. I use the on-board air to fill the tire back up. (I don't remember the pressure I used, I would think I would've filled it to the same hot pressure as the mating dual, but I'm not sure... I don't think I would've filled it to only 100 PSI at that point.)

I get back on the road, using the TPMS to keep an eagle eye on that tire, and the pressure never wavers. After a fuel stop and a total of 87 miles since the topoff, with the tire pressure still at the topped off pressure, I hear a bang, the TPMS immediately starts beeping, and the tire reads 0 PSI. I immediately pull over, the attached picture shows the result. This is the inside driver side dual, the blowout is on the side facing the outer tire.

With no slow leak warning, I don't know how long that tire was low before the alert sounded. I could've been driving on it for a while that way. Reading one of your blog entries where you say the damage that causes a blowout could've been done some miles earlier, do you think that initial low pressure might've been the cause of my blowout? Or is it just age? (The tires showed no signs of sidewall cracks.) Or both?

I am looking for a new TPMS, one with replaceable batteries. You can bet a slow leak warning is now on my requirement list!

Yes initial run low could have done the damage. Inflating the tire after running low but not having clearly identified the cause of the initial air loss IS VERY DANGEROUS. People have been killed when a truck tire sidewall ruptures. Your tire lost more than 20% of its inflation so oficially had been run "flat" which means it should have been dismounted and inspected by tire shop.

Also you were filling up a warm tire. I bet you only added enough to get you to 100 when warm which could be below 90 when at ambient.

The picture does have some signs of sidewall flex failure. I would need more pictures to be more confident of my analysis.

NOTE Sidewall cracking from UV and Ozone is not the cause of sidewall blowouts. The sidewall cracks are just a symptom of age and use. Much like when your Dr takes your temperature. The Temperature is NOT the problem just an outward indication of an inner problem.

[Tireman9]

Originally Posted by Woofer-01

I'm asking this first... what is the manufacter recommended pressure for the rear tires? Next the tire manufacturer - What is the max pressure for this tire?
Then conjecure on my part...
Any chance you had a rock wedged between the dual'lys?

I went back and downloaded the picture and tried a closer look.

Now for today's lesson class.

1. It appears the body cord are not steel but textile (Nylon or Polyester are most likely)

2. There appears to be signs of melted and fused cord similar to this


or this



The only way I have ever seen cord in this condition is from running at highway speed while significantly underinflated.

I don't think the cause was a rock caught between the duals as I don't see signs of sidewall abrasion as seen in this picture.


Note the rough surface in my picture while the original complaint tire has a smooth sidewall.


RE YOUR SAFETY

Please go to THIS RMA web site and then select Inspection Procedures to Identify Potential Sidewall. This is a FREE download and shows serious injury that can occur. It looks like you are buying the publication in that they have you put in shopping cart but it is free. Then READ the SAFETY WARNINGS

[ShapeShifter]

Originally Posted by Tireman9

Your tire lost more than 20% of its inflation so oficially had been run "flat"

Thanks for your input! I'd like to know how you came up with that 20% number. I want to learn, and there must be something I'm missing.

My pressure calculations based on actual weights put the minimum tire pressure at 90 PSI. When I stopped to check the tire, it was in the high 80s, which I figure is about a 3% loss.

My target pressure to give some headroom is 100 PSI, so from there it's about a 13% loss.

Neither one puts me at over 20% loss. And since the calculated minimum pressure is 90 PSI, wouldn't that be the figure that determines the percentage of under inflation (3% in this case?)

Also you were filling up a warm tire. I bet you only added enough to get you to 100 when warm which could be below 90 when at ambient.

I don't recall the actual pressure I used, but being aware of the pressure difference of a hot tire, I'm positive that I measured the pressure of the mating dual and filled the tire to that pressure so that both duals were the same.

BTW, that's why I'm a strong proponent of a TPMS system where you manually program in a desired tire pressure, not one which automatically programs itself according to the tire's current pressure when the sensor is installed. With a system like that, when I took off the sensor to measure the other dual's tire pressure, it would've reprogrammed the TPMS to the hot tire's pressure.

I would need more pictures to be more confident of my analysis.

Sorry, that's the only one I have.

NOTE Sidewall cracking from UV and Ozone is not the cause of sidewall blowouts. The sidewall cracks are just a symptom of age and use.

I understand. I only made that comment because I mentioned the tires were six years old, and I wanted to stem off the comments from people who would assume they were UV damaged and falling apart by that age. I did not mean to imply that it was or was not a factor in this incident.

Originally Posted by Tireman9

This is a FREE download and shows serious injury that can occur. It looks like you are buying the publication in that they have you put in shopping cart but it is free.

No, it's not free, it asks for a bunch of personally identifying information before you can download it.

[kidoo]

Originally Posted by harleyjt

This has nothing to do with rubber stems or metal stems......

Has anyone else seen this system - "Wasp" on ebay? It appears to be nearly identical to the EEZ TPMS. Only the name is changed. One other think I really like is their 6 sensor system displays all tires simultaneously. That is the one thing I would like to see in a TPMS system, rather than one that scrolls through each tire one by one. They have other systems with various numbers and combinations of sensors as well, but they scroll through one by one.

I just thought it was interesting that this one is the same as the EEZ. Same Chinese factory selling their goods to someone else..

Gulf Stream Newmar Tiffin RV Motor Home Feed Through Sensors | eBay

jt

Pretty much like this OEM in China, Aliexpress, half price from EEZ??

Truck Use 6 22 External Sensor TPMS( Tire Pressure Sensor System)-in Alarm Systems & Security from Automobiles & Motorcycles on Aliexpress.com | Alibaba Group

[vettenuts]

I am reading this with a lump in my throat. Last summer, my left front was deflated to just over 40 psi during a 100 mile drive (this is one of the reasons I purchased a TPMS over the winter). I didn't know it at the time and found it when I got home (mistake #1). I then re-inflated to 95 psi when the tire cooled (mistake #2). Not realizing the tire should be inspected, I took the coach on a 3,500 mile trip to the upper peninsula of Michigan (mistake #3) a month later.

I called the tire facility this morning that originally installed the tires about inspecting this tire after reading some of the above information posted by Tireman9. The tire facility said they would do the inspection, but since I had driven it so far without an incident the tire is likely fine. We are leaving in two weeks for another trip. This time I will have my TPMS installed but I am thinking it might be worth it to have the tire inspected before we leave.

Thoughts?



Just shows how naive one can be to the complexities of these coaches. I know I am and am thankful to have a source of information with this forum.

[Dr4Film]

Originally Posted by docj

I'm actually thinking of buying a second TPMS monitor and installing it in the toad full-time. My toad is a 2014 Honda CR-V which has what I consider to be a useless TPMS system which uses the ABS system to detect minute changes in wheel diameter caused by loss of pressure. The system is prone to false alarms and can't tell you which wheel is low. It is the most disliked feature on the 2014 CR-V (previous models had a different system).

If TST will sell me a second monitor I will install it in the CR-V permanently so I can ignore the factory system altogether. I could take the monitor out of the MH but then it would beep continuously because it would fail to get signals from the MH's sensors. I would hate to have to reprogram it every time I switched it back and forth. There is a way to get it to ignore the toad's sensors when it is away from the MH but I don't think the reverse is possible.

Originally Posted by Knightab

I don't think you need a second monitor though, the toad can be turn off from monitoring so I would think the coach could also. Before you buy a second monitor I would check this out unless you just prefer to have the second monitor and I can understand that, sometimes it is just easier.

Originally Posted by docj

After posting this I decided to call TST. They will sell a monitor alone for $59 and Mike confirmed that there is nothing wrong with what I'm proposing. Mike says he gets lots of complaints from people about how poor their car TPMS systems are.

Originally Posted by docj

I already called and spoke with Mike at TST and I asked that exact question. The answer was "no" there is no way to turn off the MH tires and just have the toad's active.

Originally Posted by Knightab

Bummer!

I would be VERY surprised if the TST TPMS does NOT have a drop & Hook feature that allows you to choose what set of tires to monitor, Coach & Car, Coach only or Car only.

The Tire SafeGuard has that feature as does the old Doran TPMS that I owned first which was useless. I would not own a TPMS without it.

If the TST TPMS truly does not have that feature that would definitely be a deal breaker for me.

Dr4Film ----- Richard

[Knightab]

Originally Posted by Dr4Film

I would be VERY surprised if the TST TPMS does NOT have a drop & Hook feature that allows you to choose what set of tires to monitor, Coach & Car, Coach only or Car only.

The Tire SafeGuard has that feature as does the old Doran TPMS that I owned first which was useless. I would not own a TPMS without it.

If the TST TPMS truly does not have that feature that would definitely be a deal breaker for me.

Dr4Film ----- Richard

I'm sure it has where you can drop the towed, so I would think if you put the monitor in the towed and drove off it would not even see the sensors on the rv.