TL;DR: ---tab Description--- 4" / 5" Turbo-Back Exhaust for 2013–2018 Dodge Ram 6.7L Diesel DPF Race Pipe vs Downpipe-Back vs Turbo-Back Exhaust Feature DPF Race Pipe Downpipe-Back Exhaust Turbo-Back Exhaust (4"/5") Start Point Replaces only the DPF section Starts after the downpipe (mid-section) From turb…