Originally Posted by Airdale
Initial testing before the tire is put into full production and then the follow-up DOT certification tests required by the FMVSS.
Ahh, thought that was what you were thinking.
DOT does not run certification tests.
It is the tire manufacturer's responsibility to "certify" that all tires made
would be capable of passing the minimum test requirements as published by FMVSS. Now as to pre-production testing, that should be based on statistical analysis of the variation of test results observed by the tire company on it's own products.
The DOT requirements do not allow for variation. They say 100% of tires must be able to pass the tests. Tire companies know that test results do in reality vary.
If you have a volume of data that tells you that your product varies by x amount then a competent company should allow for that variation such that statistically speaking say 99.95% would pass. However I would not be surprised to learn that some companies cut corners and are satisfied with a prediction that say 60% or 80% will pass as they are betting that no one will check.
They also know that if they have no warranty and the RV community will not file enough complaints to get the attention of DOT, there will never be a compliance test run by DOT so the company can "get away with" making less than 1st class quality products.