Defective tire or incorrect diagnosos? (Part 2)

Last time, I discussed how a defective tire could be made. Today I want to show how a failure that is the result of external cause can be easily misdiagnosed. Since there are so many different possible external causes I will only be able to cover a few of the multitude of possible external causes. Please note that these pictures are only a few of those collected during my investigation and many times an on-hand examination is necessary to arrive at the real reason.   Lets start with the example from last post.

Here we see a tire with a sidewall split.

Here is an X-Ray showing the broken bead wire

 

 Here we see the ends of the bead wire showing tensile (pulling) not cut ends.

 Here we see a special tool used to measure wheel diameters. If the wheel were of correct diameter the front piece would line up with the slot in the back piece.

This shows the same tool on a reference rim and you can see an in specification wheel.

While this is an extreme example I think you can agree that the engineers at the car company who are responsible for the wheel being made to specifications didn't want to accept the possibility that their manufacturing plant had made a mistake.  I liken this to RV owners who do not want to accept the possibility that by driving at speeds higher than the tire is rated for or at lower pressure or higher load they might have contributed to the tire failure.

Here are so other examples. 

This tire had physical evidence of puncture and run low but the owner wanted to claim the tire was 100% OK up until the instant the tread came off.

This tire had numerous marks of damage on the inside proving run low.

The tire with this tread throw had an old un-repaired puncture with signs of sidewall contact with part of the vehicles.

 In closing I think a review of an earlier post of a "blowout" will show you that it is a rather common mistake to incorrectly identify the reason for a tire failure.