What does an L5P delete kit include?
A complete L5P delete kit from EGR Performance includes a 4-inch mandrel-bent DPF delete pipe in T304 stainless steel, an EGR cooler delete or bypass assembly with CNC-machined 6061-T6 billet aluminum block-off plates, high-temperature Viton O-rings, and a CAN Bus plug for clean electrical integration.
Some kits also include a downpipe section and all necessary mounting hardware, gaskets, and clamps for a direct bolt-on installation.
Depending on the package, a DEF system bypass may also be included to eliminate the need for Diesel Exhaust Fluid.
Each kit is engineered for a specific year range of the 6.6L Duramax L5P, so fitment is precise and requires no modification to surrounding components.
How much does it cost to delete an L5P Duramax?
The hardware cost for an L5P delete varies depending on whether you choose a full bundled package or individual components, and the 6.6L L5P also requires an ECM unlock before tuning can begin.
That ECM unlock is handled through an E41 upgrade kit or a year-specific unlocked ECM, which is an additional step compared to earlier Duramax generations.
Professional installation labor, if you choose not to do the work yourself, will add to the total investment.
EGR Performance offers free shipping on all orders, a 45-day return policy, and a one-year warranty on every kit in this collection.
Do I need an ECM unlock to delete my L5P Duramax?
Yes. The 2017 and newer 6.6L Duramax L5P uses a locked ECM from the factory that prevents aftermarket calibration from being loaded.
Before any delete tuning can be applied, the ECM must be unlocked using either an E41 upgrade kit or a replacement unlocked ECM that matches your specific model year.
This is unique to the L5P platform and does not apply to earlier Duramax generations like the LML or LMM.
The unlock process is handled during the tuning phase, and your tuner or kit supplier will guide you through the correct path for your truck.
Attempting to run a deleted L5P without the proper ECM unlock will result in fault codes, derate modes, and drivability problems.
What years does the L5P Duramax delete kit fit?
The 6.6L Duramax L5P engine was introduced in 2017 and continues through the current model year in Chevy Silverado and GMC Sierra 2500 and 3500 series trucks.
Delete kits are segmented by generation to account for differences in exhaust routing, EGR cooler design, and ECM calibration strategy.
The 2017 through 2019 L5P trucks share one hardware configuration, while the 2020 through 2023 models use revised components that require different fitment specifications.
Some kits in this collection cover the full 2017 through 2022 range, while others with integrated downpipe sections are specific to the 2017 through 2019 generation.
Always verify your specific model year against the compatibility table before ordering.
Will an L5P delete kit improve fuel economy?
Many L5P owners report measurable fuel economy gains after a complete delete and proper tuning, primarily because the engine no longer needs to run periodic regeneration cycles that inject raw fuel into the DPF.
Removing the EGR system also reduces intake charge temperatures, which allows the engine to operate more efficiently under load.
However, actual fuel savings depend heavily on your driving habits, the tune you select, and whether you tow regularly.
Some experienced diesel technicians caution that fuel economy alone should not be the primary reason for deleting an L5P.
The more consistent and tangible benefits are reduced maintenance costs, lower exhaust gas temperatures, and the elimination of emissions-related component failures.
Can I install an L5P delete kit myself?
A mechanically experienced owner with standard hand tools and a decent jack stand or lift setup can handle the physical installation of an L5P delete kit in a full weekend.
The 4-inch DPF delete pipe is a direct bolt-on replacement that uses the factory exhaust mounting points and requires no welding or fabrication.
The EGR cooler delete involves removing the factory cooler assembly and installing precision-machined block-off plates, which takes more time but follows straightforward mechanical steps.
The tuning portion requires a Windows laptop and careful step-by-step execution of the instructions provided by your tuner.
EGR Performance provides 24/7 live support for fitment questions and post-install troubleshooting if you run into any issues during the process.
What problems does the stock L5P emissions system cause?
The factory L5P emissions system introduces several documented failure points that affect high-mileage and heavy-use trucks well before the engine itself wears out.
The EGR cooler is susceptible to cracking from thermal cycling, which can dump coolant into the intake manifold and cause hydro-lock in extreme cases.
The DPF clogs progressively, especially on trucks that see frequent short trips or operate in cold climates, triggering forced regeneration cycles that raise exhaust gas temperatures and waste fuel.
Carbon buildup from EGR recirculation coats the intake manifold and valve surfaces, gradually restricting airflow and degrading throttle response.
Industry data suggests many 2017 through 2024 L5P trucks will experience at least one emissions-related failure before reaching 125,000 miles.
Is it legal to delete an L5P Duramax?
Removing emissions control equipment from any on-road vehicle registered for highway use in the United States violates the federal Clean Air Act and is enforceable by the EPA with significant civil penalties.
L5P delete kits from EGR Performance are manufactured and sold strictly for competition and closed-course off-road use only.
Installing these components on a truck that is registered, licensed, or operated on public roads may result in failed inspections, fines, and the inability to register or sell the vehicle in jurisdictions that enforce emissions standards.
Fitment of these kits varies by model year, and each buyer is solely responsible for understanding and complying with all applicable local, state, and federal regulations before purchase and installation.
EGR Performance makes no representation that these kits are legal for street-driven vehicles.
What tuning is required after deleting an L5P Duramax?
After physically removing the DPF, EGR, and DEF hardware, the factory ECM calibration must be replaced with a delete-specific tune that disables the corresponding sensors, monitors, and diagnostic routines.
Without proper delete tuning, the truck will throw fault codes, enter limp or derate mode, display warning messages on the dash, and may experience hard starting, poor shift quality, and significantly reduced power output.
The L5P requires an ECM unlock before any custom calibration can be loaded, which is accomplished through an E41 upgrade kit or an unlocked replacement ECM.
Several reputable tuning solutions exist, including remote custom tuning services and pre-loaded calibration devices.
EGR Performance offers 24/7 live support to help coordinate the tuning process alongside your hardware installation for a seamless result.
Will an L5P delete kit void my factory warranty?
Installing a delete kit on your L5P Duramax will void the emissions-related portion of your factory warranty and may affect the powertrain warranty depending on the specific claim and your dealership's stance.
Under the Magnuson-Moss Warranty Act, a dealer must demonstrate that an aftermarket part caused a specific failure to deny coverage, but delete hardware directly modifies the emissions systems that are covered under separate federal warranty mandates.
If your truck is still within the factory five-year or 60,000-mile emissions warranty period, weigh the trade-off carefully before proceeding with a delete.
Many owners choose to wait until the factory warranty expires before performing the modification.
EGR Performance backs every kit with a one-year warranty, free shipping on all orders, and a 45-day return policy so you can purchase with confidence.
