L5P Duramax Tuning Instructions
Please read every step before making any modifications to your truck.
Prerequisites
Start with all emissions installed and functioning without codes or error messages. Be sure the DEF level is not low. On 17-19 model years, you need to make sure the soot levels are below 70% before proceeding.
Install VCM Suite BETA software. (Verify that you have the latest BETA version.) After installing the software, follow our L5P Unlock Tool Kit Cable Installation Instructions & File Preparation guide to get the files we need for your tune.
Important Notes
Use a battery charger capable of supplying 10+ AMPs.
VCM software may open the last file used, please close that file when you open VCM software (top left Folder icon).
If emissions sensors were unplugged before tuning, you will likely get a "Service Emissions" message on dashboard. Make sure your DEF tank is at least 1/4 full when you start the process. On 17-19 model years, make sure the soot level is below 70% ( A higher than 70% soot level will require a force regen before tuning).
