Interesting read. It's about Ford but thinking other makers will have some similar guidelines. There is a link to the actual Ford document in the article.
https://jalopnik.com/how-a-car-company-decides-if-its-going-to-warranty-your-1821736111
https://jalopnik.com/how-a-car-company-decides-if-its-going-to-warranty-your-1821736111