GM E42 ECM Service (L5P, Global B) - Upgrade Only

Tune your 2024 and newer L5P Duramax. The refreshed HD trucks moved to GM's Global B electronics and the E42 engine computer, which has to be upgraded before it can be tuned. This one-time HP Tuners send-in service upgrades your original ECM so you can calibrate, data log and flash through the OBDII port with VCM Suite.

This is a send-in service. Your ECM has to come out of the truck and ship to HP Tuners, so the truck will be down while it's away. Please read this whole page before ordering.

Will it work on my truck?

• 2024-2026 Chevrolet Silverado and GMC Sierra 2500HD/3500HD 6.6L Duramax (L5P)
• 2024-2026 Chevrolet Silverado and GMC Sierra 4500HD/5500HD/6500HD 6.6L Duramax (L5D)

2017-2023 L5P trucks use the E41 ECM. See our GM E41 ECM Services (L5P) or the E41 Upgrade Kit instead. For transmission tuning on the 10-speed, see the GM T93 TCM Service (Global B).

What else you'll need (sold separately)

• 8 Universal Credits to license the E42 ECM.
• An HP Tuners MPVI3 or MPVI4. Global B vehicles do not work with the MPVI2 or MPVI2+.
• The latest VCM Suite BETA software (free from HP Tuners) and an internet connection.

How it works

1. Confirm your truck is covered and place your order. Have your VIN handy; HP Tuners requires it.
2. Our team emails you the order number and the HP Tuners shipping form.
3. Remove the ECM, pack it carefully with the completed form inside, and write the order number on the outside of the box.
4. Ship it to HP Tuners with any carrier. Shipping to HP Tuners is the customer's responsibility; the shipping charged at checkout covers the return trip.
5. HP Tuners upgrades the ECM and ships it back.
6. Reinstall it, license it with 8 Universal Credits and start tuning.

Ship to:
HP Tuners, LLC
ATT: GM E42 ECM Service (L5P, Global B)
[Your order number]
711 Dartmouth Lane
Buffalo Grove, IL 60089

Wait for our email before you ship. Please don't send your ECM until you have the order number and shipping form.

Before you ship: important

• Send the original ECM from your truck. Spare ECMs are not accepted under any circumstances.
• ECMs with broken locking tabs or connectors will not be accepted.
• Do not install and relearn a spare ECM while yours is away. If you do, your upgraded original will no longer work in the truck.
• After reinstalling, connect with VCM Scanner and read and clear codes first. The truck may need a dealer resync; that is the owner's responsibility.
• Once upgraded, the ECM can only be tuned through the OBDII port with HP Tuners software. Scan tools and dealer diagnostics keep working, and you can return to stock any time with VCM Suite.
• This service is performed at the owner's risk. Normal wear and weathering from the ECM's location in the truck is expected.