6.6L GM Duramax L5P (2017–2023)

6.6L GM Duramax L5P (2017–2023) Performance Parts

The 6.6L Duramax L5P is GM's most capable diesel truck engine to date, and it is also the most emissions-restricted platform in the Duramax lineup. If your 2017 to 2023 Chevy Silverado or GMC Sierra 2500HD or 3500HD is due for a performance upgrade, EngineGo carries fitment-specific parts confirmed for the L5P platform. Exact truck fit. Complete kits. Fast U.S. warehouse shipping.

2017 to 2023 Duramax L5P Collection Highlights

Every product in this collection is matched to the 2017 to 2023 6.6L Duramax L5P platform. The L5P carries a different emissions architecture than earlier Duramax generations, and parts from LML, LMM, or LBZ trucks do not cross over to this platform. Each listing here is confirmed for L5P-equipped Silverado and Sierra heavy-duty trucks.

L5P Duramax DPF Delete Pipe: 4-inch delete pipe options built and routed for 2017 to 2023 L5P Duramax trucks.
L5P Duramax EGR Delete Kit: EGR valve and cooler delete kits with block-off hardware confirmed for 2017 to 2023 Silverado and Sierra 2500HD and 3500HD trucks.
L5P Duramax All-in-One Delete Kit: Complete EGR, DPF, DOC, and DEF delete bundles with downpipe options sized for the L5P exhaust system.
L5P Duramax Downpipe: True 3.5-inch mandrel-bent downpipes designed to replace GM’s notoriously restrictive factory pancake downpipe—drastically lowering EGTs right at the turbo flange.
Duramax L5P Exhaust System: Downpipe-back exhaust delete systems with and without muffler for 2017 to 2023 L5P-equipped trucks.

Performance Parts Built Around the L5P Duramax Platform

The L5P Is a Different Animal Than Earlier Duramax Trucks

The Duramax L5P introduced a new level of factory power output when it launched in 2017, but it also brought a more complex emissions system than any previous Duramax generation. The turbo outlet configuration, downpipe sizing, and EGR architecture on the L5P are unique to this platform. Parts listed for LML or LMM trucks will not fit. Parts listed broadly as "Duramax" without a confirmed generation callout are a fitment risk on this engine.

Important: Products in this collection are built for 2017 to 2023 Chevy Silverado 2500HD and 3500HD and GMC Sierra 2500HD and 3500HD trucks equipped with the 6.6L Duramax L5P engine. Confirm your cab, bed, and exhaust configuration before ordering. Some products cover specific year ranges within the 2017 to 2023 window. Check each product page for exact year compatibility before purchase. If your truck has prior exhaust or emissions modifications, contact EngineGo support with your full configuration details (including your 9th injector plug preference) before ordering.

The L5P collection at EngineGo covers the key upgrade categories this platform calls for. The 3.5-inch downpipe is specific to the L5P turbo outlet and is a starting point for exhaust work on these trucks. Downpipe-back exhaust systems are available in 4-inch and 5-inch configurations with muffler and without muffler options to match your build goals. EGR delete kits address the valve and cooler with the correct block-off hardware for the L5P. All-in-one delete bundles combine the downpipe, DPF and DOC delete pipe, and EGR hardware into a single fitment-confirmed purchase.

Every product page lists what ships in the box. Pipes, clamps, gaskets, block-off hardware, and downpipe components are all detailed before checkout. Installation difficulty is noted. Tuner requirements are called out at the product level because the L5P requires custom calibration.

PLEASE NOTE: 2017–2023 L5P models utilize a factory-locked E41 ECM; custom tuning strictly requires an HP Tuners (or equivalent) unlocked ECM swap or bench-unlock service prior to flashing—and that is not a detail that should show up after you order.

All products ship from U.S. warehouses with same or next business day processing on most orders.

Why L5P Duramax Owners Buy from EngineGo

Fitment Precision for the Most Complex Duramax Platform

L5P owners are not casual shoppers. They own one of the most capable diesel trucks GM has ever built, and they have usually done significant research before they land on a parts decision. They know the L5P is different. They know the downpipe sizing matters. They know a tuner is required. What they need is a supplier who has done the same homework and built their listings around the actual platform.

EngineGo is that supplier.

Products listed and confirmed for 2017 to 2023 6.6L Duramax L5P trucks
L5P-specific downpipe sizing called out clearly, including the 3.5-inch turbo outlet fitment
Year-range compatibility notes within the 2017 to 2023 window on every applicable product
Full breakdown of included parts before checkout: pipes, clamps, gaskets, block-off hardware, and downpipe components
Tuner requirement flagged at the product level, not buried in the return policy
Installation difficulty noted so you can plan the job and account for downtime
EGR, DPF, and DOC delete options available individually or as bundled kits
45-day authorized returns on qualifying orders
Free shipping within the continental United States
U.S. warehouse fulfillment with fast order processing
Support available before and after purchase for fitment checks, year-range questions, and L5P-specific install guidance

The buyers who come to EngineGo for L5P parts know what they are looking for. EngineGo makes sure they find the right product for their exact truck the first time.

Complete Your L5P Duramax Build

The L5P exhaust upgrade path starts with the downpipe. The 3.5-inch L5P downpipe connects to the turbo outlet and sets the foundation for the rest of the exhaust system. A downpipe-back delete system addresses the DPF and DOC further down the exhaust path. An EGR delete kit handles the cooler and valve side. A tuner manages calibration across all of those changes.

The L5P Duramax All-in-One Delete Kits bundle the downpipe, DPF delete pipe, and EGR hardware together so every component in the system is sourced from a single fitment-confirmed purchase.

You can also browse the full Duramax delete kit collection, Duramax exhaust options, Duramax EGR delete kits, Duramax delete pipes, and Duramax downpipe options for additional L5P and multi-generation Duramax parts.

Shop 2017 to 2023 6.6L Duramax L5P Parts at EngineGo Today

Your 2017 to 2023 Silverado or Sierra with the L5P Duramax is a serious truck. It needs parts confirmed for its exact platform, not a broad Duramax listing that leaves the generation unspecified and the downpipe sizing up for debate.

Check the Vehicle Fit Guide on each product page, confirm your cab, bed, exhaust configuration, and exact model year before ordering. The L5P has year-specific fitment notes within the 2017 to 2023 range, so reviewing each product page before checkout matters. If you are unsure which kit fits your exact setup or your truck has prior modifications, send your full truck details to EngineGo support. The team will confirm the right fit before you buy.

Shop 2017 to 2023 6.6L Duramax L5P Performance Parts and get your diesel setup ready for heavy-duty competition sled pulling, high-boost dyno builds, or dedicated closed-course setups where permitted.

Some products in this collection are intended for off-road, race, or non-public-road use where permitted. Customers are responsible for confirming compliance with federal, state, and local laws before purchase and installation.

6.6L GM Duramax L5P (2017–2023) Performance Parts

Downpipe-back Exhaust System DPF Delete 4" for 2020-2026 Chevy Silverado/GMC Sierra 2500HD/3500HD 6.6L Duramax L5P

Downpipe-back Exhaust System DPF Delete 5" for 2017-2019 Chevy Silverado/GMC Sierra 2500HD/3500HD 6.6L Duramax L5P

EGR Valve & Cooler Delete Kit for 2017-2026 Silverado/Sierra 2500HD/3500HD 6.6L Duramax L5P

EGR/DPF/DOC Delete Kit for 2017-2019 L5P 6.6L Duramax | 5" Downpipe-Back without Muffler, EGR Delete, 3.5" Downpipe

Downpipe-back Exhaust System DPF Delete 4" for 2017-2019 Chevy Silverado/GMC Sierra 2500HD/3500HD 6.6L Duramax L5P

Downpipe-Back Exhaust DPF Delete 4" & EGR Delete Kit for 2017-2019 Chevy Silverado/GMC Sierra 2500/3500HD 6.6L Duramax L5P

EGR/DPF/DOC Delete Kit for 2017-2019 L5P 6.6L Duramax | 4" Downpipe-Back without Muffler, EGR Delete, 3.5" Downpipe

3.5" Catless Downpipe for 2017-2026 Chevrolet Silverado/GMC Sierra 2500HD 3500HD 6.6L Duramax L5P

EGR/DPF/DOC Delete Kit for 2017-2026 L5P 6.6L Duramax | 4" DPF Delete Pipe, 3.5" Downpipe

DPF & Cat Delete Pipe 4" for 2017-2026 Silverado/Sierra 2500HD/3500HD 6.6L Duramax L5P

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