Duramax L5P Tuning, with NO ECM SEND-IN!

Flashpaq 2848-DS for 2017-2019 Duramax L5P with In-Field ECM Unlock Cable

We’ve been tuning the 2017-2019 L5P with great power increases for about two years, but this will still be big news for anyone who owns one.  2017-2019 L5P GM Duramax Flashpaq performance programmer (PN 2848-DS) now includes hardware and software to UNLOCK THE ECM IN THE FIELD, which means it is not necessary to remove the ECM from the vehicle and send it in.  This also means we can tune your truck in minutes, with NO VEHICLE DOWNTIME. As always, our device comes preloaded with tunes for various purposes, from performance, towing, or better fuel economy, and the Flashpaq for L5P can add up to 150 horsepower and 350 ft-lbs. of torque without ever turning a wrench. It has never been easier to add real power to an L5P Duramax!

NOTE: Each Flashpaq kit will only be capable of unlocking one vehicle.


Tune File Name                        HP            TQ

Heavy Tow                              75              150

MileageXS                              100             200

Tow Performance                125             250

Performance                          150             350


 Optional Adjustments With Tuning

  • Rev Limiter, Raise
  • Speed Limiter Disable
  • Adjust Throttle Sensitivity, +5 to +50% over stock
  • Tire Size Speedo Calibration 26”-38”
  • Gear Ratio Calibration, 3.42-5.15:1
  • Idle Speed PARK/Neutral +/- 400 RPM
  • Remember Last Button Setting – Tow/Haul and Exhaust Brake Enable


Quick Options (Reflash of ECM tune not required)

  • Temporary idle up for winch/elec. Accessories, 600-1800 RPM
  • Allison Transmission Relearn
  • Manual and Mobile DPF Regen
  • Independent Adjustment of TPMS Threshold for Front & Rear Axles, 1-90psi

Additional Features

  • Kit includes wiring harness and software to unlock vehicle ECM with NO SEND-IN REQUIRED
  • Color screen and user-friendly menus for painless programming
  • Easy updates with our software and any Mac or Windows PC
  • Vehicle parameter monitoring capabilities and Advanced Data Acquisition (PIDs)
  • Reads & clears trouble codes (CELs)
  • Tunes are compatible with other performance upgrades


ECM Unlock Instructions: Unlock_Cable_Installation_L5P_17-19_brandless