The factory LML down pipe makes an abrupt directional change immediately after the turbine flange, which restricts exhaust flow and impedes performance. The indentations in the piping can further impede exhaust flow.

Upgrade your Duramax with the PPE Free-Flow Downpipe and eliminate the rusted, restrictive factory design. The PPE Down Pipe highlights unrestricted 3-inch diameter flow path all-along, fully machined and TIG welded upper and lower flanges, and three-inch 304 stainless steel piping. It ensures smooth transitions for unobstructed exhaust flow. To further enhance performance, it comes with a woven titanium sleeve that effectively insulates heat, protecting the engine bay.