HP Tuners Releases Direct OBDII Upgrade Option for 2018-2023 GM L5P/L5D Diesel Tuning

Direct OBDII Upgrades Now Available For GM’s E41 ECM

BUFFALO GROVE, IL, June 5th, 2025—HP Tuners proudly released a new way for customers to upgrade the GM E41 ECM in their 2018-2023 Silverado/Sierra L5P/L5D diesel truck directly through the OBDII port. This new option allows customers to upgrade the ECM using only an MPVI3 OBDII device or HP Tuners’ newest RTD4 device, VCM Suite (BETA) software, and (6) Universal Credits to license the ECM—no send-in upgrade service or ECM removal necessary.

This applies to the following models:

• 2018–2023 Chevy Silverado / GMC Sierra 2500–3500 6.6L Duramax (L5P)
• 2019–2023 Chevy Silverado / GMC Sierra 4500–6500 6.6L Duramax (L5D)

Note: For customers with a 2017 L5P model, this year still requires either the HP Tuners GM E41 ECM Upgrade Kit or the one-time, send-in GM E41 ECM Upgrade Service. Both of these options will remain available on HP Tuners’ website for purchase.

In addition to this new upgrade option, HP Tuners has reduced the licensing cost for the GM E41 ECM to only (6) Universal Credits compared to (8) Universal Credits previously, saving customers $100. HP Tuners also reduced the cost of their GM E41 ECM Upgrade Kit to $199.99 compared to $349.99—$150 in savings.

Once users upgrade their ECM, they will have full access to VCM Suite for DIY tuning and diagnostics. Users can expect significantly improved write/flash times with this new option.

On the first write/flash:

• Write Calibration Only: Now 1.5 minutes vs. 12 minutes previously
• Write Entire: Now ~5 minutes vs. 12 minutes previously

For all subsequent writes/flashes:

• Write Calibration Only: Now ~40s vs. 1.5 minutes previously
• Write Entire: Now ~4 minutes vs. 6.5 minutes previously

Upgrading this controller via the OBDII port has several noted advantages, including significantly improved write times, no ECM removal, no shipping hassle and associated cost, and lower cost to get started in tuning this application.

For new customers looking to tune their 2018-2025 Silverado/Sierra L5P truck, HP Tuners’ offers an MPVI3 + (6) Universal Credit bundle to get users started.

ABOUT HP TUNERS—HP Tuners is the leading diagnostic and calibration solution for vehicle aftermarket performance with over 20 years of expertise. From diagnostics, data logging, scanning, custom calibration, and more, HP Tuners offers the most comprehensive solution for OBDII-equipped import, domestic, and powersports vehicles. Connect with HP Tuners at www.hptuners.com.