HPTuners L5P and L5D Duramax Tunes

Auto Diesel Systems is proud to offer HP Tuners L5P Modified ECM solutions for your 2017+ Chevrolet Silverado / GMC Sierra 2500/3500 6.6L Duramax. Unlock the full potential of your diesel truck with complete tuning control through OBD2 calibration, logging, and scanning.

Two Purchase Options Available

Option 1: Modified ECM Purchase
Purchase a ready-to-install HP Tuners Modified ECM from us and keep your original ECM as a backup. This is our most popular option for quick turnaround.

Option 2: ECM Exchange Program
Send us your original ECM and we'll exchange it for a HP Tuners modified unit. Both options provide full access to calibrate, log, and scan via the OBD2 port with your MPVI2 and VCM Suite 4.3+.

Important: If purchasing Option 1, do NOT send us your ECM.

Licensing Requirements

• ECM (E41) License: 8 Universal Credits
• TCM (T87A) License: 4 Universal Credits (optional, for transmission tuning)

Available Power Levels

We currently offer the following ECM tune files to match your performance goals:

• Stock (0hp) - Baseline tune
• +45hp - Mild performance upgrade
• +75hp - Balanced power and reliability
• +90hp - Noticeable performance gains
• +120hp - Aggressive street performance
• +150hp - High-performance street/tow
• +180hp - Maximum performance

Transmission Tuning (TCM)

Our TCM files are custom-built to suit your specific setup and include critical line pressure improvements to handle the added power reliably. Protect your investment with proper transmission calibration.

What You'll Need

To effectively tune your L5P Duramax, you'll need:

• MPVI2 Tuning Interface (one unit can tune multiple trucks)
• HP Tuners Modified ECM (and TCM if tuning the transmission)
• Canbus connection plugs
• Tune file and required credits to flash the controller