4-Inch T-409 Stainless Steel DPF & Cat Delete Pipe

The Spelab 4-inch Downpipe-Back DPF Delete Race Pipe is engineered to unlock the true potential of your 2020-2025 L5P 6.6L Duramax engine. By eliminating the restrictive factory Diesel Particulate Filter (DPF) and catalytic converter, this race pipe significantly reduces exhaust gas temperatures (EGTs), leading to improved turbo spool-up and throttle response. The mandrel-bent construction ensures maximum flow efficiency, allowing your diesel to breathe easier. Constructed from durable 2mm thick T-409 stainless steel, this pipe offers excellent corrosion resistance and longevity. The 4.0-inch inlet diameter is optimized for performance builds, while the T-409 stainless steel material, though magnetic, provides a more affordable alternative to T-304 with robust corrosion protection. Installation is straightforward, typically taking about an hour with basic hand tools. Clamps, hangers, and hardware are included, though some factory hardware may need to be reused. Cutting may be required for shorter wheelbase configurations. **Important Fitment Notes:** This kit is designed for 2020-2025 L5P Duramax Crew Cab configurations, including both short bed and long bed models. It does NOT fit Cab & Chassis models. Furthermore, it will only fit models equipped with the OEM style 4-bolt flange off the turbo direct pipe. The Spelab downpipe must be installed first, as the factory downpipe has an integrated SCR assembly and cannot connect directly to this rear exhaust section. **Tuner Required:** Removal of emissions control systems like the DPF, CAT, SCR, and DOC involves eliminating related sensors. A DPF delete capable tuner is essential to prevent check engine lights or diagnostic trouble codes from triggering. This modification is intended for off-road use only and may not be legal for sale or use in certain regions due to emissions regulations.