HEAT! Yes, heat is the most likely culprit for a tire breaking down. What causes heat to a tire, and what is too much heat? The compounds that make up a tire can start breaking down when you hit just north of 200 degrees. Each tire can be a little different, but if you have a tire hitting 200 degrees you are in the danger zone. There are many things that can cause a tire to heat up. The first one is the obvious, and that is ambient temperature. If you are traveling through Arizona in the middle of the summer, then your tires are going to take a beating from the heat. Another thing that causes tires to heat up is low tire pressure, but why is that?
I have always known that low pressure will drive the heat up on a tire, but I never really questioned the science behind it. When a tire is properly inflated it has a specific size tire footprint that sits on the roads surface. A properly inflated tire will have the least amount of rolling resistance, and therefore the least impact as it relates to heating up the tire. Now let’s say you are running 10 psi under pressure for the load that you are carrying. The tire footprint on the road's surface is now larger, and therefore the rolling resistance is greater, and this is what drives the heat up.
TechnoRV does a lot of business with Pressure Systems International (P.S.I.). This is the company that owns TST TPMS, and they are the largest manufacturer of auto inflation systems in the trucking industry. P.S.I. knows tires and employs some of the most knowledgeable tire engineers in the business. I got the chart below from P.S.I. and this is a result of their own testing. Note that this example is for a tire that should be at 100 psi, and the tests show how the tire footprint gets larger the more the tire is under inflated.
In this example, there is 18% more rubber on the ground on a tire that is 30% under inflated. Of course, this also has a negative impact on your fuel economy. If you are going down the road and run over a nail and develop a slow leak, you can see how just 30% under inflated has massive effects on the tire. Inflation goes down, the tire heats up, and again, around 200 degrees the tire starts to break down and this is usually when the blowout occurs.
This is the very reason that I am constantly teaching RVers about the importance of a good tire pressure monitoring system. Most blow outs are preceded by low pressure and high heat, and a good tire pressure monitoring system will alarm you of these occurrences as they are happening. For those of you that run a TPMS, you know what I mean because I get the emails from you detailing out the instances that your TPMS alarmed you in time for you to get off the road to prevent a blowout. Yes, a TPMS costs some money, but I am telling you, the peace of mind of knowing you will be alarmed of low pressure and high temperature conditions is priceless. Yes, TechnoRV sells TPMS systems, and we are confident that the TST system is the best one on the market.
Click here to check them out on our site, and order one today!