We bought a 2003 Nissan Altima new. We had the oil changed every 3000 miles and took excellent care of this vehicle. In March 2013 the engine started making rattling noises. We ended up having to add a quart of oil about twice a week just to stop the rattling. There was no leak and we saw no evidence of it burning oil. We dropped it at a Nissan Dealer in Thornton CO on our way out of town on June 18th of this year (2013). We were shocked when we rec'd a call from the dealer telling us the engine was ruined. Supposedly the catalytic converter had "disintegrated" into the engine!! The total cost of repairs was quoted at nearly $7000. We left the car with them to repair and it is now the 26th of August and we still don't have it back. Does anyone know if there is any recourse with Nissan. It sounds like there is a common theme when it comes to the engine on these 2003 Nissans. I would like to know if anyone has considered a "class action suite".