Collection: 2024-2025 L5P GM Duramax 6.6L - Exhaust Systems

Built to fit. Built to last. This is the 2024–2025 L5P exhaust lineup from Dieselr — engineered for performance and tested on real trucks.

We’ve gathered the best-performing 4-inch and 5-inch exhaust kits for the latest 6.6L GM Duramax L5P. Whether you’re looking for a full downpipe-back setup or just a precise-fitting CAT & DPF race pipe, you’ll find it here — all in stainless steel and mandrel-bent for optimal flow.

This collection includes:

• Dieselr 4” and 5” stainless downpipe-back kits
• 3.5” Dieselr aftermarket downpipe
• Polar Diesel high-flow exhaust pipes
• Full exhaust system components for a clean, leak-free install

Each product in this 2024–2025 L5P Exhaust Dieselr collection is designed for exact fitment on the newest L5P platforms. No bending, no hacking, no drama. All clamps, hangers, and welds are engineered to last — not just to bolt on.

Whether you're pairing these with our HP Tuners ECM unlock service or prepping for a full tuning package, this is the hardware you need to get the airflow right.

Trusted by real diesel techs. Tested on real builds. Order your L5P exhaust system from Dieselr today.