2018-2023 GM 6.6L L5P Duramax Engine Tuning
Level 1 - Optimized for Heavy Towing
$849.99
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2018-2023 GM 6.6L L5P Duramax Engine Tuning
$849.99
Overview
2018-2023 GM 6.6L L5P Duramax Engine Tuning is built for drivers who want a calibration that feels strong, smooth, and predictable in real-world use. Whether the vehicle spends its time commuting, towing, traveling, or being enjoyed on the street, the calibration is matched to the application and the way you use it. Final calibration details are handled through The Tune Shop's remote-tuning process.
Compatible Platforms
- HP Tuners
- EZ LYNK
Power Level Options
Choose the calibration level that best matches how you use the vehicle. Power gains are not advertised because actual output varies with the vehicle, modifications, fuel, operating conditions, and supporting hardware.
- Level 1: Optimized for Heavy Towing
- Level 2: Optimized for Light Towing
- Level 3: Daily Driver / Economy
- Level 4: Street Performance
- Level 5: Max Effort / Track
- All 5 Power Levels — includes all five calibration levels so you can select the calibration best suited to the way the vehicle is being used.
Vehicle Compatibility
- Make: Chevrolet and GMC
- Models: Silverado 2500, Silverado 3500, Sierra 2500, and Sierra 3500
- Engine: 6.6L
- Controller / Engine Code: L5P
Important Fitment & Licensing Notes
- Supported tuning platforms: HP Tuners, EZ LYNK.
- Unlock / upgrade requirement: This application requires the referenced controller unlock or upgrade service before tuning. Select the required service in the product options when applicable.
- HP Tuners licensing: 4 credit(s) are recorded for this application. Credits are separate from the tuning service.
- EZ LYNK licensing: 10 token(s) are recorded for this application when EZ LYNK is selected.
What's Included
- Custom engine calibration for the selected power level.
- Remote-tuning support for the vehicle and its supported modifications.
- Calibration revisions as reasonably needed to complete the initial tuning process.
What Customers Are Saying
- “The biggest difference is how much smoother and more responsive the truck feels in normal driving.”
- “I wanted something that behaved well while towing and still felt strong unloaded. The calibration feels very well rounded.”
- “The one-on-one support made the process easy, and the truck drives the way I wanted it to.”
Why Choose The Tune Shop?
The Tune Shop is built around personalized, one-on-one service rather than a one-size-fits-all file. We work with you to understand how the vehicle is used, the modifications it has, and the drivability you expect. Our calibrations are developed with real street use in mind and are intended to deliver smooth, predictable performance across daily driving, towing, highway use, and spirited driving while keeping the calibration matched to the vehicle's actual setup.
SOTF / Switchable Tuning
SOTF / Switchable Tuning is available as a tuning-level variant on this product. This application uses HP Tuners native SOTF.
SOTF / Switchable Tuning provides multiple calibrations that can be selected without reflashing the ECM between supported tune positions. Where five positions are supported, the selectable calibrations follow the same general progression as The Tune Shop's individual Level 1 through Level 5 tunes.
- Selectable positions: 5 custom tune slots plus stock slot
- Supported platform for switchable tuning: HP Tuners
- Switching method / hardware: OEM steering-wheel/cruise controls; HP Tuners L5P Diesel Switch optional and sold separately
Switching hardware, tuning devices, controller services, cables, credits, and licenses are not included in the SOTF tuning-service variant unless explicitly stated and remain separate selections where applicable. “All 5 Power Levels” remains a separate option that supplies the five individual non-switchable tune files.
Vehicle Information
Tuning Device*
Please choose a tuning device.
Read the vehicle with a compatible MPVI interface, upload the read/file to The Tune Shop, receive the tuned file, and flash it with HP Tuners VCM Editor.
Connect a compatible MPVI or RTD interface to The Tune Shop through HP Tuners Tune Delivery Network (TDN) for remote tune delivery.
HP Tuners Credits
EZ Lynk Tokens
Controller Upgrade
Please select an option for Controller Upgrade.
Overview
Application-specific six-position rotary switch for compatible GM L5P Duramax calibrations using HP Tuners Switch on the Fly support.
Key Features
- Six-position rotary control
- Five-foot OBD-II pass-through cable
- Knurled aluminum knob and marked position dial
Compatibility
Designed for supported 2017 and newer Chevrolet Silverado and GMC Sierra trucks with the 6.6L L5P Duramax and the required HP Tuners controller configuration. This switch is application-specific and is not interchangeable with Cummins versions.
What’s Included
One GM L5P Diesel Switch assembly with integrated OBD-II pass-through cable.
Requirements
Compatible HP Tuners interface, supported Switch on the Fly operating system, and any required E41 controller upgrade or licensing.
Important Notes
Confirm controller, operating-system, and model-year support before installation. This hardware does not include a calibration, controller service, or credits.
Transmission Tuning
Optionally add compatible transmission tuning to your engine tuning order.
Select the transmission installed in your vehicle. If you are unsure which transmission you have, contact The Tune Shop before ordering.
Please select an option for Transmission Tuning.
Transmission Tuning Platform
Transmission Licensing
No Additional Transmission Licensing Required
Transmission Tuning Platform
Transmission Licensing
Acknowledgements
I certify that this vehicle is intended for off-road or competition use only, or that the requested calibration complies with all applicable federal, state, and local emissions regulations. I understand that The Tune Shop will not provide emissions tampering calibrations for vehicles operated on public roads where prohibited by law.
- Stock Read Required: I understand that I must submit a stock read file or the required vehicle/ECM read information before custom tuning can be created. Tuning cannot begin until the required information has been received.
- Custom Vehicle-Specific Tuning: I understand that all tuning is custom-made specifically for my vehicle, regardless of whether the vehicle is stock or modified. I am responsible for providing complete and accurate information regarding the vehicle, installed modifications, and current configuration.
- Initial Tune Turnaround: I understand that the initial custom tune typically requires 3–5 business days to complete after all required files, read information, and vehicle information have been received.
- Tune Revision Turnaround: I understand that requested tune revisions may require up to 2 business days to complete after the necessary datalogs, feedback, or other requested information has been submitted.
By checking this acknowledgement, I confirm that I understand these requirements and turnaround times and agree to provide all requested information necessary to complete my custom tuning.