What is that?

We were cruising along a freshly paved section of road out in the country at 60 mph pulling the tear when suddenly I heard a strange noise followed by a low rumbling sound like a diesel engine with a mild jake brake. I did not feel a thing change in the car. There was construction equipment all around on the sides of the road, but it was Sunday. A few seconds later I checked my rear view mirror. Please keep in mind my rear view mirrors are what I call dental mirrors. They are not much bigger than a dental mirror and are 90% useless.

In the mirror all I could see was a circle of smoke. I pulled over quickly and was heading for the fire extinguisher in the galley. To my surprise the street side tire on the tear was not on fire (no flames), but it was putting out enough smoke to be illegal. It was time to be glad we decided to purchase that spare tire from CI.

Inspection showed the outside wall blew out (30#’s air pressure) and then the wheel proceeded to cut up the inner wall in at least six places and was trying to destroy the whole tire. It still had over half of the tread left at 24,700 miles.

The tire went from just fine to smoke city in 2/10’s of a mile at 60 mph. No vibration, no swaying, no fishtail, no drag, just a little noise. If the radio had been turned up and we went another 1/4 mile it would have been time to get out the marshmallows and call Cary to order a new one. Oh, I forgot it was Sunday.

Hilditch, 1%er

 

This happens on big rig RV's as well - on 5th wheels you feel NOTHING - I know - I hit a bridge and never knew it! Tire Pressure Monitoring systems can be purchased to keep an eye on your trailer tires and might be worth it to someone. I have one but Bill misplaced the instructions! Yes, I'm blaming him! Not planning on installing it though - our son has a 5th wheel so he's inheriting it - he's the mechanical one in the family and figure out how to use it! But tires blowing out is a serious problem with RV'ers - it's discussed on other forums quite frequently. If you don't keep an eye on those rear tires you can damage the trailer significantly. Many others have...

 

Well the classic answer ("...horses, not zebras"; or "Occcam's razor," take your pick) would follow this line of reasoning. You glanced in the mirror within seconds of the sound (the blowout, followed by the typical sound of running on a flat) and saw smoke that had been generated within the few seconds preceding or following the blowout. Thus the tire was already very hot at the moment of blowout. Typical cause for that would have been running for minutes or more at very low pressure. My conclusion: Leak or low pressure in the proceeding minutes you hadn't noticed, you ran on it for minutes or longer, and it overheated and blew out. Likely caused by puncture and/or slow leak. Less likely, it could have been caused by tire ply delamination that generated heat running under load, although today's better tires seldom fail by delaminating the way they did when I was a youngster. That you had 30psi last time you checked was irrelevant if you had either of those failure causes.

 

Au contraire Jim. You said; "(the blowout, followed by the typical sound of running on a flat)" Not true at all when the blowout is behind the vehicle you are riding in. Not typical at all. The tire was not hot at the time of the blowout as a blowout does not occur at low air pressure or when the tire gets flat. You are just making stuff up Jim.

Hilditch

 

Wow, clearly my mistake not to look for zebras. My apologies for replying; won't happen again.