S400 Second-Gen Turbo Kit

The Smeding Diesel S400 Second-Gen Turbo Kit is engineered to unlock maximum power and airflow for your 2003-2007 Dodge Ram 5.9L Cummins. This comprehensive kit provides a perfect balance of durability, drivability, and raw power, suitable for towing, daily driving, or high-horsepower builds. Assembled and quality-controlled in the USA, it’s built by diesel enthusiasts for real-world drivers. The kit includes everything needed for a bolt-on installation: an S400 turbocharger (available in multiple sizes like S464/83, S467/83, S472/83, S472/87, with cast or billet wheel options), a T4 3-piece exhaust manifold for second-gen placement, a 4-inch downpipe for improved exhaust flow, a 5-inch intake kit with a filter for maximum airflow, and all necessary oil feed/drain lines, intercooler piping, and hardware. Customize your performance by selecting your desired turbo size and exhaust housing size, with options including .90, 1.0, and 1.10 A/R for precise spool, towing power, or top-end performance tuning. The second-gen turbo location, combined with the 5-inch intake, ensures your Cummins breathes cool, clean air, contributing to lower Exhaust Gas Temperatures (EGTs). This kit is specifically designed for the 2003-2007 5.9L Cummins. While the S400 frame is capable of supporting 600-1200+ HP, it's important to note that single S400 turbos are not ideal for general towing or daily driving due to noticeable lag below 2,000 RPM; for such applications, S300 single turbos or compound turbo systems are recommended.