I own a 2010 Prius. There is
I own a 2010 Prius. There is a very common problem with the factory pistons and rings failing after 100k or so and burning oil. I've had the head gasket replaced at the dealer under warranty at 148k, and it did not fix the rattle on startup problem or the oil consumption problem. Toyota knows about these problems. I had to fight to get them to honor their CA emissions warranty for the head gasket but would not do anything about the burning oil problems.