L5P 6.6L Duramax 5" Downpipe-Back DPF Delete Exhaust for 2017-2019 Chevy/GMC

This L5P downpipe-back kit is designed as a bolt-on system for most wheelbase configurations. It utilizes high-quality clamps to secure the 409 stainless sections. However, depending on your specific cab and bed length (e.g., Regular Cab vs. Crew Cab Long Bed), some trimming of the extension pipe may be necessary to achieve a perfect fit.

By removing the restrictive factory baffling and filters, backpressure is significantly reduced. This allows the turbo to spool up faster and, more importantly, shed heat much more efficiently. Lowering the thermal load on the turbocharger bearings is one of the most effective ways to prevent premature turbo failure in high-output Duramax engines.

Because this is a Straight Pipe (Muffler Delete) system, the exhaust note is significantly louder than stock. You will hear a distinct "hum" or drone at highway speeds, especially when the engine is under load or towing. If you prioritize a quiet cabin for long-distance family road trips, you might consider adding a high-flow muffler; but for those seeking the raw L5P sound, this is the ultimate setup.

409 Stainless Steel is chosen for its functional durability rather than mirror-like aesthetics. While it is much more corrosion-resistant than aluminized steel, it will develop a brownish surface oxidation (patina) over time due to heat cycles. It is not intended to be polished to a chrome shine, but it provides superior protection against road salt and grime.

Yes, this system is engineered with precise mandrel bends to follow the factory exhaust routing. While the 5-inch diameter is significantly larger than stock, it is designed to clear the spare tire heat shield and rear shock absorbers on standard height and most leveled L5P trucks. However, if you have an aftermarket oversized spare tire or custom long-travel suspension, we recommend verifying clearance during the mock-up phase of installation.