What's a Duramax LML Delete Kit?
An LML Duramax Delete Kit is a performance upgrade that removes restrictive emissions hardware to unlock horsepower, improve fuel economy, and prevent engine downtime.
This Duramax EGR delete kit solution is designed specifically for 2011-2016 GM applications, including late-model 2015.5-2016 Duramax LML trucks.
What's Included in a Duramax LML All-in-One Delete Kit?
Each Duramax LML All-in-One Kit includes a performance tuner, a DPF-delete exhaust pipe, and EGR block-off hardware to improve fuel economy and prevent emissions-related downtime.
- Tuning: Custom calibration to disable DEF/DPF/EGR sensors and prevent engine limp mode.
- DPF delete exhaust systems: A high-flow 4" or 5" straight pipe to replace the restrictive DPF and SCR components.
- EGR delete kits: Precision-cut block-off plates to eliminate soot buildup in the intake.
Key Benefits of Installing a Duramax LML Delete Kit
An off-road Duramax Delete Kit optimizes your truck’s performance by removing restrictive emissions components, significantly improving reliability and efficiency for heavy-duty use.
- Reliability: Eliminate DEF/DPF sensor failures and the dreaded limp mode shutdowns.
- Fuel Efficiency: Stop wasteful regen cycles to boost fuel economy in automobiles.
- Engine Longevity: Prevent soot recirculation inside the EGR system on Duramax.
- Lower Costs: End the need for DEF fluid and expensive emissions system repairs.
- Performance: Improve turbo spool and throttle response by reducing backpressure.
- Better Cooling: Drop EGTs by removing restrictive factory filters and hardware.
Duramax LML Delete Kit: Deleted vs. Stock
| Dimension |
Stock (Factory) |
Deleted (Upgraded) |
| Horsepower |
Factory rated at 397 HP; often feels detuned due to emissions-focused calibration due to conservative emissions mapping. |
Increased; Custom tuning typically adds 50–150+ HP, depending on tuning level and supporting modifications. |
| Fuel Economy |
Average; efficiency is lost to frequent DPF regeneration cycles and exhaust restriction. |
Improved; Removing the DPF and stopping regens typically results in a 3–5 MPG increase, depending on driving habits and tuning. |
| Maintenance Cost |
Very High; Requires regular DEF refills and is prone to expensive DPF/EGR sensor repairs. |
Reduced; Eliminates the need for DEF and removes the primary causes of engine "limp mode." |
| Reliability |
Moderate; Emissions components are high-failure items; CP4 pump remains a known weak point. |
Significantly Enhanced; Removes failure-prone emissions gear. |
| Exhaust Gas Temp |
High; EGTs spike during active regeneration to burn off soot in the filter. |
Lower EGTs; Improved airflow allows the engine to run 100–200°F cooler under load. |
| Legal Status |
Street Legal; EPA and CARB compliant. |
Off-Road / Competition Use Only. |
GM DURAMAX LML 6.6L Models Year Fitment Guide (2011–2016)
Choose the perfect duramax LML delete kit by model year to guarantee seamless fitment and performance.
| Delete Kit |
Model Year |
Emissions Systems |
Common Issues |
Recommended Setup |
| 6.6L GM Duramax LML Delete Kits (2011–2016) |
2011–2012 |
EGR, DPF, DEF (SCR) |
Frequent regen cycles, DEF system faults, injector issues, high EGTs |
Full Delete Kit (EGR + DPF + DEF) with supported tuning |
| 2013–2014 |
EGR, DPF, DEF (Updated sensors) |
DEF warnings, sensor failures, regen downtime |
Year-Specific Full Delete Kit with compatible tuning |
| 2015–2016 |
EGR, DPF, DEF (Updated ECM strategy) |
Stricter ECM control, limited tuning support |
Vetted Full Delete Kits for Supported Applications |
How to Install an LML 6.6L Duramax Delete Kit
Installing an LML Duramax Delete Kit is a key reliability upgrade, focusing on removing the DEF system and EGR components. Proper ECM tuning and removal sequence are critical to the process.
Installation Steps
- ECM Preparation & Tuning: Begin with ECM calibration using a supported tuner to disable emissions systems electronically.
- Emissions Exhaust Removal: Remove the factory exhaust containing the DPF delete and SCR components.
- Performance Exhaust Installation: Install the new straight pipe exhaust system designed for factory hangers.
- EGR System Delete: Use block-off hardware or full removal to prevent soot recirculation.
- Final System Check: Clear diagnostic codes and verify turbo boost, exhaust temps, and drivability.
Note: Every EngineGo kit includes a comprehensive, model-specific guide to ensure your installation is seamless and your fitment is guaranteed. For technical deep-dives, step-by-step photos, and specific torque specs, you can find detailed information under the "Installation Guide" tab on every product page.
Why Choose EngineGo for Duramax LML Delete Kits
Choosing EngineGo means partnering with diesel performance experts. We back every build with technical support, ensuring your truck moves from the shop to the street with peak power and reliability.
15+ Years of Expert Support
In-House Specialists: Our team has over 15 years of hands-on experience in Ford Powerstroke, Cummins, and Duramax platforms..
Expert Guidance: We provide comprehensive support, from initial fitment questions to final tuning advice.
High-Performance Reliability
Built to Last: We pride ourselves on offering parts designed for maximum durability and long-term reliability.
Expertly Vetted: Every product is backed by our deep understanding of diesel engines.
A Seamless Shopping Experience
Free Shipping: Many of our kits include free shipping to get your project started without extra costs.
Money-Back Guarantee: Shop with confidence knowing your purchase is protected if you aren't satisfied.
Off-Road Use Disclaimer
Diesel delete kits are intended for off-road and competition-use vehicles only. These products are not legal for use on public roads and are sold strictly for non-emissions-controlled applications.
Always verify and comply with local, state, and federal regulations before purchase or installation.
FAQ
Is a delete kit legal for my LML Duramax?
No. Removing emissions components like the DPF, DEF, or EGR is a violation of the Federal Clean Air Act. These kits are strictly intended for off-road, competition, or closed-course use. Using a deleted truck on public roads can lead to heavy fines and failure of state emissions inspections.
Will an LML delete fix the CP4 fuel pump issue?
No. While a delete makes the engine more reliable by removing emissions-related failures, it does not address the CP4 high-pressure fuel pump weakness. Many LML owners choose to perform a CP3 conversion at the same time as their delete to ensure total fuel system reliability.
How much extra MPG can I expect?
Most LML owners see an increase of 3 to 5 MPG. This gain comes from eliminating active regeneration cycles (which spray fuel directly into the exhaust) and reducing the extreme backpressure caused by the factory DPF filter.
Do I need to remove the EGR cooler completely?
You have two options: a "Full Delete" (removing the cooler entirely) or a "Block-off" (leaving the cooler in place but using plates to stop airflow). A full delete is generally preferred as it cleans up the engine bay and permanently prevents coolant leaks into the intake.
Can I return my LML to stock after deleting?
Yes, provided you keep all the factory hardware (DPF/SCR/EGR) and have a tuner capable of flashing the stock file back onto the ECM. However, reinstalling these heavy, soot-filled components is a labor-intensive process.