Under Pressure, Tire stories

The number one thing (actually things) that are under pressure every day all day long is our tires.

How many RV blogs have a major multinational RV tire professional who reads and monitors the blog? We do, and now we have a major multinational tire pressure monitoring company that is also following us.

PressurePro has solved our tire pressure monitoring issues. We now have a fully functional working full-time monitor for our tire pressure and temperature that works perfectly. This has been a huge time saver and has solved a safety concern with help from PressurePro.

My RV Tire Stories

RV tires have always been an issue for us and we have addressed tires in several blog posts. The first time we mentioned our tires was while we were at our first FMCA RV rally in Coos Bay, Oregon. This story goes that we were getting some unusual wear on our passenger side front tire. Just after the rally, we had it rotated to the inside rear tire position.

When you rotate a car tire, you do both tire and wheel together. On my RV(s), you have to keep the wheel at the same location and swap only the tires. I put the tire showing wear in the rear position so that it had a buddy tire (dually tire) to help it out. When a tire is on the front axel, it is all alone on the job. The whole story about the rally is in this post. Coos Bay

During the FMCA rally in Minot, we had our tires inspected by Michelin and the representative noted some unacceptable sidewall issues. I hardly mentioned it in my review of the rally but resolved the issue in the middle of our stay in Yellowstone National Park. This story goes into details of how we ended up with an entire set of new tires both with an FMCA discount and warranty refund from Michelin (still they were expensive). Yellowstone Wins

Cutthroat Peak Washington Pass
Our RV in the Cascade Mountains.

When we sold our RV and purchased an older nicer RV, (in the above picture) with the purchase we got a tire pressure monitoring system. Here is a link to the description of our new RV (it doesn’t mention the tires). Our new RV

Taking care of your tires

Remember the Michelin tire pros who follow our blog in the Yellowstone article. In their seminar, they mentioned how the only thing that they recommend to use on the tires is tire covers. The entire purpose of the tire cover is to block the ultraviolet radiation from the sun from dry rotting the side walls.

Under Pressure our old RV tire covers.
Our RV next to the Columbia River.

The only thing they recommend to wash your tires is mild soap. How about tire dressing products? Nope. How about rubber treatment products? Nope.

Everything other than soap and water (according to Michelin) decreases the life of your tires. If you wash them or dress them with some product that causes black to transfer to the rag, then this black was removed from the surface of the tire. This black (carbon) migrated from the inside of the rubber compound to the surface of the tire. If you use a chemical that removes the carbon, the same chemical is attacking the rubber. If you want your tires to die an early death attack them with chemicals and then bake them in direct sunlight.

Parking

We cover our tires nearly every time we park for more than a two-night stay. Sometimes, however, we only covered the sunny side of the RV and sometimes we skipped covering our tires because we were parked in shadows. Sometimes we skipped covering our tires when it was raining. Other than that, we cover them all the time.

The best tire covers I have had — I made.

Maybe someday we will find a commercially made tire cover that is good, but so far the answer is DIY – you can make a better tire cover than you can buy. On our first RV, tire covers were one of the first things we ever purchased (they were not good). I modified them to have an attachment at the bottom so that they would not blow away. At least our current tire covers fit our tires (they came with our RV and I am making them work). They fit but I still don’t like them, at least they probably won’t blow away. I mentioned the ones I made, they are in the following picture.

Our RV in the California Redwoods
Our RV in the California Redwoods

Long-Term Parking

Before we were full-time RVers, we had our RV parked in storage for nearly a year. The tires were covered and we were parked on plywood that someone discarded. We also had our jacks down supporting much of the weight of the RV. Tires don’t like to sit. Tires especially don’t like to sit on concrete. They were designed to roll. So even when it was in storage we took it out for a few drives, including one wonderful trip to see the total eclipse in 2017. Here is a link to that story. Total Solar Eclipse

Who helps us with our tires?

Michelin and PressurePro. Yes, staff members at both companies read our blog. At least I think they read the blog, I send it to them each week. Perhaps they just look at the pictures. We don’t currently have Michelin tires but when we did, we were happy (we are not unhappy with Toyo — they came on the RV). We are not on the payroll of either company. As frequently mentioned, we don’t earn any money from our blog. Here are links to both companies. Michelin & PressurePro

I am so impressed with PressurePro that in the future I intend to strip most of the rest of this article out of this post and re-publish it as a stand-alone article. Perhaps PressurePro can use it as a product review. Here is a link to that shorter review. FoxRVTravel TPMS

Who is PressurePro?

PressurePro makes tire pressure monitoring systems for huge fleets of trucks. In fact, they make tire pressure monitoring systems for huge tires like you would find on heavy-duty mining equipment. My RV tires are similar to ones used on semi-trucks. PressurePro TPMS works on all inflatable tires. I’m going to try it on my bicycle tires too — just for a lark.

Under Pressure PressurePro

TPMS

TPMS is the abbreviation that stands for “tire pressure monitoring system” and I am going to start describing my systems as TMPS. Yes, I said systems. I now have five systems that monitor my tires. The only system that actually works full time every day, twenty-four hours a day, while rolling or stationary is my PressurePro TPMS.

Three tire pressure gauges and my infrared thermometer.
Three tire pressure gauges and my infrared thermometer.

Five systems?

Yes, even if you only have a car you have two “systems” (or at least you should have two). The first one is manual checking your tire pressure frequently and the second one is built into your car and is the tire pressure warning system. In all cars, your tire warning system only works when the car is running. Until now the only good way for us to monitor our RV tire pressures was to check each tire using our tire gauge before each move. Obviously, a manual tire pressure gauge only works when you are testing the tire. Our RV does not have a built-in tire warning system.

Three more systems

In addition to the above two systems, we also had three other “systems” that we used or tried to use, every time we drove the RV. The first one was an infrared non-contact thermometer. Anytime we stopped driving, like at a rest stop, I would walk around the RV and record the tire sidewall temperatures (including the temperatures on our tow car). This enabled me to verify that the temperatures were all similar thus leading me to conclude that all the tires were reacting to the heat increase about the same way. Especially if you don’t have a TPMS, I highly recommend using an infrared thermometer while at rest stops along the road.

We also have two different dashboard-mounted TPMS systems. I hesitate to mention that I have two because now I only use one. I use the PressurePro system and it works great, twenty-four hours a day. For the last year, I had a nonfunctional, nontrustworthy part-time TPMS which I replaced with the PressurePro system.

How it was

I don’t do side by side product comparisons but I am willing to tell you why my old system was not trustworthy. So here is how it didn’t work. The first component that goes into a tire pressure monitoring system, all tire monitoring systems, is the sensor. Our sensors replace the valve stem cap. Each sensor has a battery and a transmitter that sends out a signal to a receiver that then displays the information. My new PressurePro TPMS works the same way.

My RV tire with sensor on the valve stem.

In our old system, the sensors had a limited range and the rear tires were too far away, especially too far away for the sensors on the car, so the solution was to put a repeater/amplifier in the rear of the RV that would rebroadcast the signal from the sensor to the receiver. This fixed the signal strength issue.

My old tire pressure monitor and sensors (turned upside down as not to show the name). The white box is the relay box. This one is old enough that the company doesn't sell this one anymore.
My old tire pressure monitor and sensors (turned upside down, as not to show the name). The white box is the relay box. This one is old enough that the company doesn’t sell this one anymore.

Why it didn’t work

The best system fails at its weakest point. The more complex a system, the more possible failure points, and the failure point in our old system were the sensors. They frequently failed to measure the pressure and they never measured the pressure accurately. How do I know? I tested them against each other and against two different manual gauges. You might say that sometimes they were close. My old system could not be trusted, here is why.

Driving

As you drive your tire pressures go up (I will explain later). If the sensors don’t record the increased pressures then they don’t work. Sometimes when I disconnected sensors (removing the pressure) an alarm would go off on the receiver. Sometimes nothing happened. I am also going to point out that the temperature function of the sensors never worked — not even close.

So even though I had a TPMS for an entire year, I still measured the RV tire pressures manually before each time I drove the RV. During each trip, I measured tire temperatures to make sure that the temperatures stayed within safe operating temperatures. On my PressurePro I even check the sensors to find out the current outside air temperature in the morning after I wake up. Assuming they are not sitting in the sun, it works great.

PressurePro TPMS

Since switching, after a year of fighting with my old TPMS, I have checked PressurePro against my old system during installation and against manual pressure gauges in nearly all conditions (while stationary and moving) and I see what I expect to see every time I check it. Both the pressures and temperatures are exactly what I expect. After I run through tire safety stuff I will tell you how I set it up and how it works. But for now, I will leave it at… it works much better, it is hard to believe how good it works.

Under Pressure PressurePro
My Pulse FX TPMS parts. Notice the heavy grade antenna cable and antenna that I mounted near the rear tires.

Why is it a need

A good functional TPMS can help prevent tire failure. Will it prevent all tire failures? No. It will just prevent the most common cause of tire failure. I mentioned earlier, as a tire is used, the pressure and temperature of the tires increases. The reason for this is because the tire is being flexed. As the tire rolls, the side walls compress and expand on each rotation. This movement causes friction and heat as a result of the compression of the sidewall. When this happens the pressure and temperature of the tire rise.

Heavy loads or low tire pressure will increase the flex and result in greater temperature than light loads or proper inflation. You even get some friction as a part of traction on the road surface. All of this is normal. Failure in the brakes also can cause brake dragging and dramatically causes an increase in tire temperature. High temperature leads to tire failure. Everyone who drives on highways has seen large truck tires shredded tread on the roads. Nearly all these failures are related to high tire temperatures.

Riding on air

Tires provide two things, traction, (this is where the rubber meets the road) and air capture. The air inside the tire supports the weight of the vehicle. Truly you are ridding on air. This air in your tire is your first shock absorber. Air pressure is what makes the tire work. The higher the weight of the vehicle, the more air pressure is needed. If you have a heavy vehicle (RV) and have low air pressure, then you are allowing for more sidewall flex as the tire rotates and this creates higher temperature and leads to tire failure.

Under Inflation

The more your tires are underinflated, the more the sidewalls flex, and the higher the heat buildup inside the tire. Remember a few years back when there was a problem with Ford Explorers and other SUVs rolling over. These failures were nearly all related to underinflated tires.

RVs are harder on tires than semi-trucks

Semi-trucks wear out tires due to wear. RVs are rarely, if ever, driven these kinds of miles. The reason RVs are harder on tires is twofold. First RVs are nearly always operated near maximum load. Unlike an empty truck, there is no such thing as an empty RV. Second, RVers allow tires to get old before they wear out due to tread life. RVs also sit, sometimes they sit for extended periods. Tires that are not used frequently are more prone to failure (due to several different factors) than tires that are frequently used. The older your tires, the more important constant pressure monitoring is needed.

How my PressurePro TPMS works

Robust wheel sensors are installed replacing the stem caps on each wheel. These sensors transmit the information to the Pulse FX receiver module located on my dashboard right next to my gauges. The face of my module is directly in my line of sight. Attached to the Pulse FX module is the power cord, plugged into a 12-volt outlet and an antenna cable. I put the antenna under my RV mounted vertically (vertical mounting is important) near the rear tires. Running the antenna cable through my firewall along the frame to the antenna location was by far the hardest part of my install. That was it, install complete.

No Display?

That is right no display, the Pulse FX module on my dash is the best display. If the face of the Pulse FX flashes red, I have a problem.

Under Pressure PressurePro

My Other Display

My phone is the other display. The picture at the top of the post is a screenshot taken from my phone. If I get a new phone, my old phone could be a full-time display. Do I need a full-time display? I have a full-time display right on the Pulse FX module. I don’t need to have the phone display turned on while I am driving, because the Pulse FX module gives me constant monitoring.

As a side note, warnings are not instantaneous, meaning that a full blowout could occur a few seconds before the Pulse FX module turns red. If the blowout is on our car, and we are towing it at the time, the Pulse FX module may be the only way we know we had a blowout. I have seen pictures of tow cars that have been towed for miles without the RV owner ever knowing that the tow car had a blowout.

My phone serves as a good part-time display when I want to check the tire pressure before a trip and while driving my phone can give me real-time information about changes that occur. The phone even has alerts on the operation of the car tires when I am looking at the PressurePro app RV information screen. The Alert system also works when the PressurePro App is running in the background.

Under Pressure PressurePro

This alert screen happened on my primary screen with the RV tires when I took a sensor off my car identifying a critical under pressure situation. After I removed the sensor, my car display looked like this.

PressurePro screen capture showing a (simulated) critical under pressure alert in the front tire of our car.
PressurePro screen capture showing a (simulated) critical under pressure alert in the front tire of our car.

The same thing would have happened had I been looking at the car information screen and had I removed the sensor from the RV.

A similar alert would have happened if I had been looking at a different screen on my phone when the event happened.

Alerts

The Pulse FX module on my dashboard shows the alerts by turning red. You can’t see it in this picture, but for an alert, the Pulse FX module flashes. When the pressure falls 24% below the reference pressure you will get a critical alert and the Pulse FX module will flash very fast. If the pressure falls 12.5% below the reference pressure (slow leak) the Pulse FX module will flash at a slower rate. A slow Pulse FX module flash rate indicates that you need to increase air pressure in the tires. We carry a 150-psi electric pump just so we can take care of this before we start driving — right there in the campground.

Under Pressure PressurePro

When the FX flashes red, my phone also announces the alert with a notification tone anytime the PressurePro application is open. The details of the failure are on my phone.

While Driving

I took the following screenshot from my phone of the RV display after we were driving. As you can see the pressure and temperature increased from the cold reference pressure of 105 up to 114. When we were driving, the pressures were even higher at about 120-psi. The temperature has also cooled down to only about ten degrees above the outside air temperature. In this screen-capture, the sun was on the driver’s side of the RV and you can easily see the temperature difference.

Under Pressure PressurePro

About the Sensors

All the sensors are factory sealed against all moisture. Given this fact, you cannot replace the batteries. They transmit on a discrete radio frequency that will not interfere with your car tire pressure system. The sensors are designed to conserve battery life and only transmit a short distance. They transmit a pulse every 7 seconds also to conserve battery life. The sensors send the pulse every seven seconds even when they are not on the tires so removing the sensors will not improve battery life.

According to PressurePro the batteries in the sensors should last several years. One thing that will help improve battery life is to keep the sensors cool. Do not let your tires or the sensors sit in direct sun, cover them up. Heat destroys batteries, all batteries. Here is a link to my article that discusses (among other things) how to make my lithium batteries last as long as possible. Ten Lithium Battery Myths and Answer

Tire pressure, Pressure Altitude and Density Altitude

I have to say that my information on this subject is incomplete yet I’m going to mention it anyway. The way my information is incomplete is twofold. I don’t know how many different TPMS devices work this way. I know that the PressurePro system takes all of these items into account because I asked. All TPMS devices take tire pressure into account. The other two items are pressure altitude and density altitude both are in the realm of geeks and pilots (not always the same or different things).

Pressure altitude changes with weather and elevation above sea level. As you are higher above sea level or in a lower pressure airmass, the weight of the air column above you decreases. Density altitude is pressure altitude corrected for temperature and humidity (mostly temperature). As the temperature goes up, then the air is less dense, thus density altitude.

When determining if a change needs reporting as an alert, the PressurePro system, including the sensors and the Pulse FX module take the pressure and density altitude into account (I don’t know how) before reporting an alert.

About the FX Module

The Pulse FX module takes data from up to 40 tires at a time (perhaps more depending on how it is configured). The pressure range for the system is between 8 & 215 PSI. The Pulse FX module is powered by my RV 12-volt system and runs 24 hours per day. When the blue LED light on the module is solid it is paired with my phone. When the blue LED light is flashing, it is ready to pair. Honestly, I don’t look at the blue LED, but rather my phone will tell me when it is paired. One minor limitation is that the Pulse FX module can only pair to one device at a time. This limitation is a Bluetooth issue.

Final Thoughts on Tire Care

I have several thoughts at the end of this post. First, I want to take all necessary precautions while we enjoy the freedom of full-time travel. I also believe that nearly all tire problems are preventable. Having a tire blowout would really stink. I want this post to be informative but not preachy. It is not meant to be doom and gloom. I am very thankful to Michelin and PressurePro for helping me be as careful as I can be with regard to my tires. Thank you very much.

1 thought on “Under Pressure, Tire stories”

  1. On your phone, is there a screen where you can see both the RV and the tow car information all at the same time?

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