P0420 on a low mile LS1

Model: LS1 Fault Code: P0420 Posted: 2006-03-16 11:48

Im having a P0420 fault code come up. I clear it and it comes back within 2 weeks. Its a totally stock 2000 Trans Am WS6 with 62k on the odometer. I cant believe the cats are going bad this soon. I read on the code but it says how to find out if you have bat cats. What about bad O2 sensors?