'Defective’ tires: Just what is the ‘defect’?

 I have heard people claim they had a “defective” tire when they post about a tire failure. I have even addressed claims from lawyers and supposed “experts” that a group or even thousands of tires had “a defect” that caused tires to fail. However, for some reason, they can almost never point to or identify the specific component or material that contained said “defect”.

I spent the majority of my 40+ years as a tire design engineer looking at and investigating tire failures. I can say that I have identified a few tires that contained a “defect.” But before I continue we need to be sure we have a common understanding of the word “defect” and what we mean when we use it.

Definition of “defect”

Merriam-Webster says the meaning of “defect” is “an imperfection or abnormality that impairs quality, function, or utility: shortcoming, flaw.” I note that they are not saying that an item has a defect if it has failed to perform. They are talking about a specific “imperfection or abnormality” in an item.

I sometimes offer the following in an effort to clarify the concept. If we discover a dead body, should we always assume that the person was murdered? Of course not. But jumping to a conclusion about the most extreme cause seems to be what some want to do while ignoring the need for a thoughtful and reasoned collection of facts and evidence.

Tires can fail for dozens, if not hundreds, of different contributing factors, but most do not involve design or manufacturing mistakes. When I read a post on an RV forum or receive an email about a “failed” tire, I do not start with the assumption that there was a manufacturing or design mistake. I do start with a close examination of the tire, wheel, and valve, as many times the evidence is in front of our faces. The question is, are we willing to take the time and make the effort to look for the evidence that is almost always there?

Why people might use the word “defect”

I believe that many times some people use the word “defect” as they do not have the knowledge of how to do even a basic inspection. That is understandable. But if we want to avoid a repeat, wouldn’t it be best to learn the real reason for the failure and take steps to try and prevent a re-occurrence? What bothers me, though, is when I hear lawyers or reporters use the word possibly to grab the attention of those reading an article. I believe that a headline saying “Another RV tire failed, facts to follow” would not gain much readership.

In my posts on RVTravel.com and in my RV Tire Safety blog,  I have provided numerous examples of failed tires that were initially claimed to be “defective” such as the following examples.

A tire that was run with low inflation.

One that has an external cut.

Or this tire with a plug in the sidewall.

Or this tire failure below that was due to leaking air. This failure even ended up on YouTube, but the video did not mention the evidence of the tire having been run with very low air pressure.

Currently, there are news articles mentioning failures that occurred many years ago on some RV tires that might have been improperly installed on some heavy RVs. While I have no details, I do recall reading the word “defective” in the article, but no mention of what the “defect” might have been.

Did a “defect” really cause the tire failure?

I would suggest that when you read a “news” article about tire failures and find the word “defective,” you stop and see if the author mentions what the imperfection or abnormality was in the tire that caused the failure.