Only you can decide if you're going to re-invest in your vehicle or trade. However, if you consider trading, I would avoid just about all diesel vehicles from 2007-2010. These are the years in which they only had DPF systems and did not have the SCR (Urea) aftertreatment. The newest diesels (2011 and up for GM and Ford, 2013 and up for RAM) run far less EGR than those from 07-10' because of the SCR system. By running less EGR, you feed less soot back into the intake and your EGR valve is less prone to being clogged. Cummins actually had an EGR cleaning process at 75,000 miles for the 07-12 DPF-only ISB's.