The GM E42 ECM Service (L5P, Global B) is a one-time, send-in upgrade service required for the latest-generation L5P Duramax trucks equipped with the E42 engine control module (ECM).

Once upgraded, the E42 ECM can be accessed using HP Tuners’ VCM Suite for diagnostics, data logging, and supported calibration changes when paired with a compatible interface.

This service requires removal and shipment of the original ECM from your vehicle. Spare or replacement ECMs are not accepted.

This service applies only to Global B L5P trucks equipped with the E42 ECM, including:

• 2024–2026 Chevrolet Silverado 2500/3500 — 6.6L Duramax (L5P)
• 2024–2026 GMC Sierra 2500/3500 — 6.6L Duramax (L5P)

Important: If you have a 2017–2023 Silverado or Sierra 2500/3500 6.6L L5P, refer to the GM E41 ECM Service (L5P) instead. This page applies only to E42-equipped Global B vehicles.

This is a send-in upgrade service

• Remove the original E42 ECM from your truck.
• Ship it to HP Tuners for processing.
• The upgraded ECM is returned ready for licensing and use.
• Typical service time is up to 7 business days, not including shipping.
• This is an upgrade-only service. No programming changes are performed. The calibration present on the controller when it arrives will remain unchanged when it is returned.

After your ECM is upgraded, the following are required:

• HP Tuners MPVI3 or MPVI4 interface
  • Earlier MPVI generations are not compatible with Global B vehicles
• Latest version of VCM Suite (BETA)
• Eight (8) Universal Credits to license the ECM

Universal Credits are not included and must be purchased separately.

• HP Tuners supports 2020-2022 Chevrolet Silverado 1500/GMC Sierra 1500 3.0L Duramax (LM2) trucks that are non-Global B. This includes “facelift” trucks as they are Global-B and contain a different controller.
• ECMs with broken tabs or connectors WILL NOT be accepted for Upgrades.
• This service only upgrades your original ECM for tuning, it does not reprogram your ECM for a different VIN. If you intend to send HP Tuners a spare E46 ECM, it will be returned to you with the same programming as it was received and may not operate in your GM vehicle without additional programming by a GM dealer.
• Your E46 ECM core must be fully functional with no physical or internal damage.
• No other tuning or calibration tools can be used with the E46 ECM (not including dealer reflash tools).
• VCM Scanner, Dealer Diagnostic, and other diagnostic tools will continue to function normally.
• The latest version of VCM Suite can be used to return to the stock calibration and/or update to the latest stock calibration.
• The E46 ECM upgrade service can take up to 7 business days to complete (not including shipping times).
• HP Tuners’ E46 ECM support does not cover the Chevrolet Suburban LM2 at this time.

Shipping address for send-in services:

HP Tuners, LLC

ATT: GM E42 ECM Service (L5P, Global B)

700 Eastwood Ln

Buffalo Grove, IL 60089

• After purchasing this service, please fill out the shipping form below and place it inside your shipping box.
• Please allow up to 7 business days (not including shipping times) per PCM that you send in for the upgrade process to be completed.
• Any additional hardware ordered with this product will be shipped along with your controller. To avoid any delays on other products, please create a separate order for those items.
• Customers are responsible for shipping costs when sending HP Tuners your ECM/PCM/TCM. The shipping charge at checkout only covers returning your control module after modification.

This applies to international shipments only!

To avoid unnecessary tariff charges on shipping your controller to HP Tuners for servicing, please see the PDF linked below with instructions for the most popular carriers, UPS, DHL, and FedEx. Note: If you are within the US, your shipment will not be impacted by tariffs.

• These ECM/PCM/TCM services are completed at the owner’s risk. HP Tuners will not be responsible for the vehicle, its powertrain, or electronics, nor how the control module is used, calibrated, and its functionality.
• Due to the factory location of the controller in the vehicle, all ECM/PCM/TCMs will exhibit signs of weathering and wear, which is completely normal.
• When utilizing this service there is a possibility that the vehicle will need to be sent to the dealers to be re synced. Purchaser accepts all liability for this activity.

Should you experience any issues with your controller, please submit a ticket to our support team for assistance on how to proceed.

HP Tuners designs and manufactures software and hardware tools for vehicle diagnostics, scanning, logging, calibration, and data acquisition purposes. The authorized use of such tools is to bring a motor vehicle into emissions compliance and/or to maintain emissions compliance, as well as for use on competition/racing and other exempted vehicles. HP Tuners does not create or provide tunes or pre-made calibrations.

HP Tuners’ Terms of Use, policies, and agreements mandate that users shall comply with all local, state, and federal laws. In using HP Tuners software and hardware tools, you are representing, warranting, and agreeing not to use, employ or allow any HP Tuners tools to operate as a defeat device or to violate emissions compliance in any manner whatsoever. You further represent warrant and agree that the HP Tuners tools shall only be used by manufacturers, calibration businesses, and professionals to develop emissions-compliant and/or exempted calibrations.