I had a flat today. I think I caught it quickly because the tire still had a fair amount of air in it. Once I noticed the flat, I stopped within a 1/4 mile.
I noticed that the sidewall of the flat tire is badly cracked; almost all the way around. This picture is not my tire, but it is similar. The cracking is in the same place, possibly a bit closer to the outside of the tire. I checked the other three tires and they all appear fine.
The tires are not all that old; I estimate around 20k miles. I do not rotate them. I also do not park or rub along curbs. The bad tire was the driver’s front.
What are some possible causes of this type of cracking? I’d like to understand if it is something I could have caused before I take it into the store.
I’m sorry I don’t have the exact tire details. I bought them from Sam’s Club and they might be Firestone. They are for a 2006 Honda Accord V6.
I suspect it was caused by chronic under-inflation, possibly aided by long-term exposure to strong sunlight and/or vapours of chemicals unfriendly to rubber.
Cracking can be a sign of age and light exposure. You say the tires are not that old, but you don’t know how old the tires were when you purchased them. There are movement on to restrict the sale of tires beyond a certain “SELL BY” date based on manufacturing date.
If your flat tire really had the appearance of the picture posted, this cracking is more likely due to fatigue caused by under-inflation rather than age cracking. Running low makes the tire flex more, but the heat build up is the real source of deterioration.
Most of us tend to neglect tire pressure. Once you get tuned in, you can observe a low tire by eye if it gets to the danger point. I carry a digital gauge and an electric pump.
Tire age is determined by knowing how to decipher the DOT stamp on the sidewall. Tire Rack has a good explanation.
Given that the car is a 2006, though, tire age isn’t the likely culprit here, since even the OEM tires would be 4 years old, and the OP stated these had been purchased.
I agree that under-inflation is the most likely cause. I’m amazed at the casual attitude people have towards their tires. I’m sure I’m a little more anal than normal on this topic, but I can name the size, brand and model of every tire on our 4 vehicles. I check the PSI in each car at least every couple of weeks, if not every fill-up.
Two most important things on your car: brakes and tires.
In the end those two systems are all that keep you from carnage and death!
Not saying the OP is negligent, don’t know him/her, but almost every day I commute to work, I can look around in traffic and spot at least one car with bald or under inflated tires.
As for what caused it to crack? Heat. Tires get warm even in regular usage, spirited driving can heat them up more, and under inflation multiplies that heat. Eventually leading to breakdown of the rubber and chemical compounds on the sidewall
That does not look consistent with ozone degradation of the rubber.
Tires are typically a blend natural and synthetic polymer. Natural rubber has little ozone protection by itself. Carbon black is added to give the polymer ozone resistance and strength.
I found my warranty. The tires were on the car for 18 months and were manufactured just 22 months ago (44th week of 2008). The tires have about 20k miles.
I’m not real anal about checking the pressure, but I don’t ignore it either. It has been a hot summer.
Approximately how long would the tire have to be driven under-inflated for it to fail?
It can happen pretty quickly. Either you let that tire get under-inflated relative to the others (unlikely) or you ran over a nail or something which resulted in a slow leak. Either way, a few miles of high-speed driving is enough to overheat an under-inflated tire and cause the damage you see.
Either way, it is not the tire shop’s responsibility, and there is nothing wrong with the tire.
In addition to the overheating, the cracking comes from the tire’s sidewall flexing under the weight of the car and being “creased” against the road.
