Help Needed - CE Light with P0430/0420 Codes and UltraGauge Question

Hey guys, long story short, i JUST got my truck back from having the frame replaced, and the CE light came on at the dealer, they told me about it and cleared the code. About 30 miles later, it was back on, and has been on for the last two days. My truck sat in their lot from the middle of November until now, but prior to taking it in I have never had any issues or had a CE light on.

I find it almost too much of a coincidence that I didn't have any issues until my truck was torn apart, my question is, is there anything I could do with a scan tool like an UltraGauge that could tell me if it was the actually the cats, or just a sensor? I don't really want to spend the $2k + on new cats if that isn't the issue.

Edit: I should add, there are not any signs of a rough idle, or hesitation that might indicate a clogged cat.

 

Any strange rattling noises when you rev the engine? Sometimes when the cat is bad you can hear a rattling sound. Since your getting both P0420 and P0430 makes me think it is a O2 sensor issue and not a cat issue. If you had no CE codes prior to the dealership work then I would take it back and have them fix it.

 

Definitely no rattling that I can hear, i had a cat go bad in my s-10 when I was younger so that was the first thing I checked. I ran some fuel system cleaner through thinking maybe it was just old gas even though I put stabil in when I dropped it off. I will probably go back to the dealer on Monday and see what they will do.