So my 2012 SR5 (145k) has been inactive a lot and recently the heat shields for the cats rusted off. Then the Check Engine light came on. I brought it to my small garage to see if they could fix it but they were confused since the multiple codes seemed to point to different problems. After a visit to the dealer, the diagnosis is the complete exhaust system needs to be replaced including both catalytic converters; they said the underneath was heavily rusted. Also the possibility of both manifolds if they are leaking, and this can only be determined once opened up. I'm looking at 5k CDN in repairs (3.5 without the manifolds). I'm leaning towards having it done at the dealer since the parts (although severely overpriced) are guaranteed for 2 years as well as labor. I'm thinking to have the manifolds done at the same time even if they are ok since they will probably need to be done at some point and may as well while it's opened up. My worry is if I go for aftermarket parts, the catalytic converters are still pricey and may only get me so far. The body has no rust and I plan to keep this truck forever. Any suggestions?