There was an article on the NY Times online that contained the following statement:
The article continued
The center’s report, which was sent to the Federal Trade Commission, asserted that such warranty programs were maintained by at least five automobile manufacturers: the General Motors Corporation, the Ford Motor Company, the Chrysler Corporation, the American Honda Motor Company and Toyota Motor Sales U.S.A. Inc.
What does this mean to you? You need to be aggressive in confronting the authorized dealership when they are repairing your car for repeated problems because you never know if there is a known defect for which the manufacturer is paying for claims.
You also should monitor the internet. Very frequently there will be online forums that discuss these known problems and give you information to address your authorized dealership.
Secret warranties are real and need to be addressed by any automobile owner who has confronted continued defects for which warranty coverage is denied.
The Center for Auto Safety also has a nice synopsis on Secret Warranties.
There was also a book written on this matter by Clarence Ditlow.