In April of 2000, when the car was only 4 years old, the timing chain broke for the first time, when it did it cracked the head causing the repairs to be over $600. I was told at the time that it was very unusual for a car that was that 'young' to break a timing chain, especially under 100K miles. It was fixed anyway, at my cost because it was no longer under warranty. Now, in September, just slightly over a year later, our car was making noises again and we took it in before it broke down, to learn that AGAIN it was the timing chain, and it needed to be replaced. This time, even without the broken head, it is going to cost us over $600 to fix because of the area we live now. I was told by the dealership that GM has known of this problem happening for a while, but has not yet taken any action on it.