This may be rare, but it happens,, If you brng your car to the dealer for all your service, even those overpriced 30k, 60k mile services, they have gone to bat for the customer to Mazda. They may argue that they know the vehicle and service it regularly, and that such-and-such must be a defect. Not saying it happens often, but it does happenMazda noticed it was leaking by the seal, they replaced the seal. I went in for another oil change and they noticed it was leaking from the new seal. Then they realized the rear diff was bad, my Service Tech pitched a fit and I went home with a new rear diff free of charge. ** Disclaimer, I drive an average of 5000 miles and I'm their most frequent customer and have a good relationship with my Service Tech.