This is pretty weird.

Last year Ross posted a good thread about how you can read the mfg date on your tires to learn how old they are. This thread shows why you want to know that.

I got to visit the CTZCC Partz car on Saturday and noticed the R/R tire had blown out thru the thread. The entire car is up on jackstands, so there is NO weight on the tires. Tire pressure was normal at 34psi when this happened for no apparent reason.

I realiZe the pictures don't show it very well, but the force of the blowout dug a hole into the gravel driveway about 3" deep, showering dirt and gravel all over the area.

It's odd to me that the tire blew on its own, while suspended in the air with no weight on it. Also, if it had blown at any other point on the tire, there wouldn't have been such a dramatic hole under the car. Finally, I'm baffled at why a tire would fail THROUGH THE THREAD (which is pretty tough steel belted material), rather than thru the weaker sidewall.

Anyway, if this can happen to a good-"looking" Sears Roadhandler with no weight on it, you can bet Ross' article was important. This tire failed thru age alone. The whole car has not rolled a full mile in the past 20 years, and there was no weight or stress on the tire when it blew. It had plenty of tread left on it. The 4 Roadhandler radials were a very recent purchase when the car was parked for good 20 years ago.

Age kills tires. Blowouts kill people. Know the age of your tires.

Frank

Frank,
I’m far from a tire expert but I would guess the weight of the car has little or no difference in the tire pressure. How much do you think that slightly rusted Z weighs? Divided by 4 and then again by the area of the tire in contact with the road? I guess it was just time for that tire to go.

Well I'm sure no expert either, but it baffles me to picture this tire self-destructing without external pressures acting on it. I could picture it slowly deflating thru an aged valve stem, or leaking flat around the bead, or getting slowly weather-checked and leaking air out thru the cracks, or even to blow out the age-weakened sidewall if the car was resting on the tires.

But this tire just showed no signs of imminent death. In fact, three of them looked good enough for me to consider using them as shop tires after we finish picking the parts off the car. And why would it blow out thru the toughest part of the tire? If it bulged and popped out the sidewall I could undrstnd it easier than blowing out thru 4 plies of steel radial belts.

I'm still baffled.