BladeRunner Ductile Iron Ductile Iron Exhaust Manifold (46-40012) by aFe. Includes: Hardware. Features 2 EGT Probe Ports, Thick Wall Design, Matched Ports, Merged Runner Design. Replace the exhaust manifold on your Dodge diesel with the BladeRunner stainless steel manifold. It was created to address a cracking problem with the stock manifold, but its so far advanced compared to the stock unit, you should replace your OEM manifold even if theres nothing wrong with it. The BladeRunner manifold will not only last far longer, it will improve performance and lower exhaust gas temperatures.