what would you do c 15 cat problem?????

No good way out of this one ....

.does the warrantee cover the emmision system? Either way be prepared to put an art head and various sensors on every year. Change the primary fuel filter every 10k and use a cat filter. Also change the screen (filter) in the fuel supply line to the art head every 6 months. 1/2 way between art head replacments.......

You'll be lucky if this truck doesn't bury you.