Upgrade your exhaust system with the GDP 3.5" Downpipe, specifically engineered for the 2017-2023 Duramax L5P. Built to improve exhaust flow and reduce backpressure, this downpipe is the perfect solution for those looking to enhance turbo spool-up, lower EGTs (exhaust gas temperatures), and unlock more horsepower and torque from their Duramax.

Crafted from premium materials, the 3.5" diameter design ensures maximum airflow, allowing your engine to breathe better and perform more efficiently. Whether you're towing heavy loads or pushing your truck to its limits on the track, this downpipe delivers the performance and durability your L5P demands.

Note: The original part number for this downpipe, GDP45001, will be superseded by 255-01301 in the future.

Includes:

• Heat wrap for thermal protection, helping to maintain lower under-hood temperatures.
• Clamps to securely fasten the heat wrap, ensuring it stays in place even under extreme conditions.

Features:

• Improved Exhaust Flow: 3.5" diameter reduces backpressure and increases airflow for better turbo response and engine efficiency.
• Lower EGTs: Enhanced design helps lower exhaust gas temperatures, improving overall engine longevity.
• Durable Construction: Made from high-quality materials to withstand high temperatures and the rigors of heavy-duty use.
• Perfect Fit: Direct bolt-on installation for all 2017-2023 Duramax L5P models.

Unlock your Duramax’s true potential with the GDP 3.5" Downpipe and experience better throttle response, more power, and a longer-lasting engine.