By Roger Marble
I saw this post that confirms what I have suggested as a possible additional benefit to running TPMS (Tire Pressure Monitoring System).
TPMS sensors mounted on metal, bolt-in valve stems are more likely to sense the temperature of the metal wheel. They will transfer the heat from a wheel bearing or brake drag and failure better than they can report the heat generated in the shoulder of a radial tire.
Here’s the post about the TPMS alarm:
On a trip I noted that one tire was 20F more than the others. When fueling, the temperature alarm went off at 160F. The wheel and hub were very hot. We were 90 miles from the next town. I found a shop that supported Dexter. They pulled the wheel and drum and one of the brake pads with broken springs fell out. There was minimum scoring of the drum and they had the replacement brake assembly … It took an hour to fix. I would not have known this if it wasn’t for the temperature monitor. And it could have been real bad on I-10 in West Texas.
People need to realize that rubber is really a good insulator to heat transfer. The hottest spot in radials is at the belt edge, which is about 3/8″ to 5/8″ deep in the tire structure. The color thermographic picture in THIS post shows the location of the hottest spot.
The heat generated by the tire in the shoulder cannot be directly sensed or reported by your Tire Pressure Monitoring System.
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What’s the “best” TPMS? What are important features?
Thank goodness I have a TST system on my 40’DP and tow behind pickup truck. Last month (June 2021) I was on extended trip in Michigan. We had unhooked the truck to do local sightseeing and a few hours later rehooked the truck to the RV. Just prior to doing so, I made a small adjustment to the emergency breakaway system which locks the brakes. Little did I know that I had inadvertently partially applied the brakes. Luckily, my TST alerted me to high temperatures in the tires about 8 miles down the road. I had no idea as my 400hp overcame any resistance. This could have been a major disaster. TST and TechnoRV, if you read this, thank you for saving our vacation!
Had a TPMS and no problems were indicated until someone pulled alongside me, beeped their horn, and pointed to my trailer tires. I saw some puffs of smoke from the left rear tire. Wasn’t burning but the tire had blown! The TPMS finally alerted about TEN MINUTES AFTER I pulled over! Sompan said they had no clue as to why. Wish I could find out what company has a good system.
If the tire suffered a tread separation but did not lose air then the TPMS would not activate. There is no system currently in the market that I know of that warns of belt separations (“Blowout” is a catch-all for “the tire failed” and does not always mean the tire lost air.) I have suggested people do a “Free Spin” inspection as seen in the video referenced in THIS blog post AND to run an air loss TEST at least once a year to ensure the TPMS is functioning properly and to confirm you have the Low-pressure warning level only a few PSI below the minimum required to support your load. As a Firefighter, I bet you frequently tested your equipment. Same need to test your TPMS.
Understand as has been said many times, many ways, there’s no guarantees on tire life. I’m a fan of TPMS but I had a tire fail seconds after I saw normal readings displayed. I take what I consider meticulous care of my tires but I had the tire shed it’s tread in one continuous piece and the carcass blow out. The tire was visually perfect so I thought I could get extra time out of it. NOPE! It was 7 years a old. From now on 6 years and done, at least on this trailer.
Sorry to hear of your tire failure. TPMS are designed to MONITOR tire inflation and warn of leaks. They can not warn of pure belt separations. A close visual inspection, as seen in the video mentioned in THIS blog post can many times discover a belt separation before the tire comes apart in pieces.
X-2 on using an IR Temperature gun to shoot the hubs of each wheel at every rest stop. Make sure to place the gun as close as possible to the hub.
Exactly. A TPMS is best used for trend monitoring rather than absolute numbers. If all tires are displaying numbers in their normal range, life is good. It’s when a tire starts acting different than the others and/or different from where it usually displays that you should investigate further.
This example is also a good reminder why carrying an infrared temperature “gun” is a good thing, especially if you get in the habit of “shooting the hubs” on all stops.
The money, damage, and life you save may be your own.