CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Tire Down, Bumps in Sidewall, Wanting to Know the Cause

Last Wednesday afternoon, I was driving my pickup truck south on I-83 in Maryland on my way to my daughter’s house for Thanksgiving. A car pulled up along side me and the driver pointed to the rear of my truck. I waved thank you and pulled over. I found that my left rear tire was going flat. I drove about a mile to the next exit and got off to change the flat. The tire still held enough air to keep the rim about 2 inches off of the ground.

The tire was an LT265, 16 inch, load range E. It still has about 1/2 of the tread on it. I had driven about 15 miles after I left my office before the other driver alerted me to the problem. I did not notice any problems with the tire when I got in the truck and left my office to travel to my daughter’s house. Since the tire is on the driver’s side, I would probably have noticed if it was 1/2 flat. There was no load in the truck bed. I keep the tires inflated to 60 lbs.

After pulling to a safe location, I removed the flat tire and put on the spare. When I lowered the jack, I noticed that the spare was also low on air. I searched through my truck for a can of “Fix A Flat” but no luck. I checked my GPS and found the the nearest gas station was 2-1/2 miles. I decided to drive there to put air in the spare. I kept my speed below 45. About 1/2 mile from the gas station, the spare came apart.

When I arrived at the gas station, I decided to try to put air in the original tire. If it held air, I was going to put it back on the truck. The pump started and I noticed that the air pressure in the tire was zero. As the pressure in the tire rose, I noticed that it was holding air. At around 20 lbs, bumps started to appear in the side wall on the side that would have been toward the outside of the truck. At 25 lbs, they were very pronounced. There was one bump every three (approx) inches, 1/2 way around the tire. Obviously a problem with the sidewall.

I called AAA and got towed to a service center where I purchased two new tires. I still have the original tire in the back of the truck.

I would like to know if there is a way to tell if the sidewall failed and caused the flat or if low air may have caused the sidewall to fail. As I said, I did not notice a problem with the tire when I left my office. I made several stops in the AM before I arrived at the office. Didn’t notice any problems.

I would like to visit the tire dealer where I purchased the original tire and ask some questions. However, if the failure is due to low air and I missed it, then it’s my fault. If the tire failed and there is a way to know that before visiting the dealer, then I’m certain that he will help make it right.

It’s the driver’s responsibility to maintain air pressure. If you drive on a flat tire or tire with vary low air pressure, there is no way to tell which occurred first.

I’d say the sidewall was damaged due to running low on air. Either the tire was low when you left the office or you picked up a nail puncture or something while on the road. If you have a flat when a car is moving the tire will be destroyed by the time you stop the car. Sidewalls in radial tires are relatively thin and flexible and easily damaged when there isn’t any air in the the tire. Also a tire can look OK and have as little as 15 lbs of air unless you really look carefully you’ll assume all is OK.

I recently had a flat and pulled the car over to the shoulder. The tire was shredded. I can’t find any evidence of a nail hole, but that is difficult when you can’t put air in the tire and look for bubbling. I’ll never know what happened, but I had to buy a new tire that I know.

I’ve only seen blisters from hitting something, like hitting a curb at an angle. One, maybe two of them. To have them consistently about every 3" tells me something may have been mis-calibrated when producing it. It may not be impossible for blisters to form from low air & the tire heating up, but it would usually just bust up the tire, not go flat but still blister like that when air is put in. The low air could make the defect more susceptible to occur, but the main problem would still be a defective tire.

I’ve dealt with many flats before, but I won’t claim to be an expert. It’d be worth it to bring this issue up with your dealer, and maybe do some research into any recalls for that particular brand or model of tire, lest it be an issue that hasn’t been caught yet.

-J

I doubt it was a production error. If you drive on a low tire you will break the sidewalls in most cases.

Sidewall damage like you describe is almost always the result of driving on a flat or low tire. I’m sure if inspected you would find a puncture or other damage/leak in the tread of the tire, which caused the low tire in the first place.

As you found out with your spare, it only takes a mile to ruin a sidewall by driving on a low tire.

You can get a plug in 12v air compressor pretty cheap these days and they don’t take up much space.