GDP Downpipe Back Exhaust - Single (2020-2023 GM 2500/3500 6.6L Duramax L5P)

Built for Strength. Engineered for Performance.

Upgrade your exhaust system with the GDP Downpipe Back Exhaust, designed for 2020-2023 GM 2500/3500 6.6L Duramax L5P. Built from T409 stainless steel, this system enhances airflow, durability, and horsepower, making it a must-have for serious truck owners.

Why Choose GDP?

✔ Heavy-Duty Construction – Mandrel-bent T409 stainless steel ensures maximum durability and a perfect fit. ✔ Leak-Free Connections – High-quality flanges and pre-welded contour-bent hangers for a secure installation. ✔ Hassle-Free Install – Includes all necessary clamps and hardware for a straightforward installation.

Performance Benefits:

✔ Increased Horsepower – Improved exhaust flow lets your Duramax breathe better and run stronger. ✔ Lower EGTs – More efficient exhaust flow helps reduce exhaust gas temperatures, keeping your engine cooler. ✔ Deep, Aggressive Sound – Get a throatier exhaust note that commands attention.

Fitment & Compatibility:

✔ Designed for 2020-2023 GM 2500/3500 6.6L Duramax L5P. ✔ Compatible with EC-CC/SB-LB-Dually cab and box configurations. ✔ OEM-Style 4-Bolt Flange – Ensures a secure, factory-like fit. ✔ No Bungs – Allowing for customization based on your specific needs. ✔ Important Fitment Note: This system ONLY fits models equipped with the OEM-style 4-bolt flange off the turbo direct pipe.

Important Disclaimer:

⚠ Off-Road Use Only – Requires aftermarket tuning and is intended for competition use only. ⚠ Regulatory Compliance – Installation on emission-controlled vehicles may violate local laws. Check regulations before installation.

Take Your Duramax to the Next Level

The GDP Downpipe Back Exhaust delivers stronger performance, lower EGTs, and a deeper exhaust tone—all in a durable, high-quality system built for serious truck owners.