RV Tire Safety
with RV tire expert Roger Marble
I read the following on a forum for one brand of trailers where they were discussing the advantages of having a TPMS:
Someone said, “How do you know if you have picked up a nail, which is leaking air, since your last walk-around? A TPMS is like a fuel gauge. You could always dip your fuel tanks at every stop too.”
Another reader replied, “Great point; I might add, if there is something happening to the tire like tread separation which could lead to a blowout the temp likely would be going up and the alarm would sound and show temp compared to other tires…. I have read here on the Forum and other Forum’s several incidents where a blown tire has caused extensive damage. Same if you picked up a nail or something where a “slow leak” might become a fast leak after you’re back driving on the highway… Like insurance…but, maybe not worth it to some folks.”
I replied:
As a tire engineer, I am sorry to inform you that having a belt separation will probably not generate enough heat to set the TPMS warning off.
TPMS stands for Tire Pressure Monitoring System. It does not and for all intents and purposes cannot provide advance warning of a tire failure due to belt/tread separation.
Air leaks can cause failures in a few miles, as seen in my blog post on Blowout a real-life experience on an Airstream, to after a few hours depending on how fast the leak is. Some TPMSs offer warning if the pressure drops by just a couple psi in a couple of minutes or less. Some will not warn till you drop 15% to 25% below the cold inflation pressure, which means you first have to lose the pressure you gained from normal driving.
I know of no consumer-level device that can advise of a belt separation, as separation can take thousands of miles to grow large enough to result in the tire coming apart.
I have posted on this blog on how to do a thorough tire inspection to discover if you have a separation. I also posted a video and pictures of a tire belt separation before the tire came apart. I covered the “why” of tire failures in this post. Did you read and understand that information?
Read more from Roger Marble on his blog at RVtiresafety.net.
##RVT881
I have a TPMS and I was running a set of (Chinese) tires when I noticed an unusual vibration. At first, I suspected the road surface — nope. Then I suspected balance, but the vibration was at 25-35mph, too low a speed for balance issues.
Finally, I got out and physically inspected the tires: lumps on the tread surface — the beginning of catastrophic tread separation failure.
The TPMS never saw a thing — because the incipient failure had not affected temperature or pressure.
Yes, Gregg. Tire Pressure Monitor Systems cannot warn of belt separations just as your engine oil pressure gauge can’t warn you of a burnt valve. TPMS only “monitor” tire pressure. I have posted in my blog about the tire info from TPMS and how I think the temperature readings can result in some confusion or a false sense of security.
I’ll confirm… what appeared road hazard and tread-fail blowouts, TPMS didn’t see either one coming. TPMS may have helped with North/South temperature expansion, but damage failures were much too abrupt.
I’ll also second “extensive damage” phrasing…. blowout just needed new tire, but tread failure flogged $5000 worth of damage i’m still repairing…
Agree. We have a TPMS system and had a tread separation. No warning occurred at all. As recommended by Roger, we have our tires inspected regularly and ask for a spin test.
I have had three tread separations, one without TPMS and two with TPMS. There was no indication of temp or psi change before the tire came apart and extensively damaged the trailer while the tire still held air. These were Goodyear G 614, G rated tires. There was a problem with those particular tires in the mid 2000’s. On the first one I didn’t know that Goodyear was aware of the problem. After some internet research, I found out about the problem but it was too late to file a claim. The second one, I had the tire dealer file a claim for me and Goodyear reimbursed me for the tire and damage repair. The third one, I just went ahead and had the fourth tire replaced as well, Goodyear reimbursed me for the third tire and the damage again. At the time Goodyear was the only manufacturer that had a G rated tire in my size, so I was stuck replacing with the same tire. The replacement tires have performed very well since. There are some other G rated tires now available but overall I am happy with Goodyear and the tires that I have now.