Remanufactured Duramax 6.6L ECM

A rebuilt Duramax 6.6L ECM that arrives ready to fit

A remanufactured Duramax 6.6L engine control module, programmed to your truck's VIN before it leaves us. It arrives with the manufacturer's current software already loaded and is ready to fit.

Your original module stays in the truck until the replacement lands on your doorstep. The truck is only down for the fitting, not for a round trip to a bench. At Diesel ECM Exchange we work on diesel control modules and nothing else, and this page covers the 6.6L Duramax across all seven of its engine generations, from the 2001 LB7 to the 2021 L5P.

Match your truck to one of 25 Duramax units without pulling the module

Pick the option that matches your truck's model year and engine generation. We then match the part number against your VIN before the unit is programmed, so you do not have to pull your module and read a number off the label before you order.

The 25 units on this page cover seven engine generations:

• 2001-04 LB7, two part numbers
• 2004-05 LLY, five part numbers
• 2006-07 LBZ, four part numbers
• 2007-10 LMM, four part numbers
• 2010-11 LGH, one part number
• 2012 to 2016 LML, five part numbers split across four separate year groups
• 2017-21 L5P, four part numbers

Two model years sit in two generations at once, and that is where orders go wrong. A 2007 truck can carry the LBZ or the LMM. A 2014 truck can fall in the 2013-14 LML group or the 2014-15 LML group. The year on your registration does not settle either one, which is why we match on the VIN instead of taking the year at face value.

The same problem shows up in the numbers themselves. 19260753 and 19260758 are one digit apart and sit in different generations, the first in the LBZ group and the second in the LMM group. 12606126 and 12606127 both sit in the LBZ group and are two separate options. Choosing by year and letting the VIN confirm the number keeps you clear of all four traps.

GM's own parts filings name the trucks several of these later units belong to. Part numbers 12648344 and 12654088 are named against the 2012 and 2013 Chevrolet Silverado 2500, the 2013 Chevrolet Silverado 3500, the Chevrolet Express, the GMC Sierra 2500, the GMC Sierra Denali and the GMC Savana (`NHTSA-TSB:10113096`, `NHTSA-TSB:10113129`). Part number 12658036 is named against the 2015 Silverado 2500, Sierra 2500 and Sierra Denali (`NHTSA-TSB:10111954`). Part number 12662677 is named against the 2016 Silverado 2500, Sierra 2500, Sierra Denali, Express and Savana (`NHTSA-TSB:10114970`). Part number 12683624 is named against the 2017 and 2018 Silverado, Silverado 2500, Sierra and Sierra 3500 (`NHTSA-TSB:10123228`). GM designates the L5P engine control module family the E41 in the same set of filings (`NHTSA-TSB:10119030`).

The Duramax modules page lists the Duramax modules we carry.

Your old Duramax ECM becomes the core after the swap, not before

Your old module is the core, and returning it is what activates the lifetime warranty. It goes back to us after the replacement is fitted, so nothing has to come off your truck before you order.

Nothing is held up front. There is no core deposit at checkout and no money sitting against a part you have already sent away. A prepaid return label and a self-addressed envelope travel in the box with your unit, so the core costs you nothing to send.

If the core never comes back, the warranty is not activated and a core charge applies. The warranty terms set out what is covered and what the exchange requires.

Two ways to get one of these 25 Duramax units

We sell all 25 of the Duramax 6.6L units on this page two ways, and the right one depends on how long your truck can sit.

Buying the rebuilt unit outright, which is this page. Your module stays in the truck until the replacement arrives, so the only downtime is the fitting. You supply the VIN after purchase, and programming starts when it reaches us. The warranty begins once the old core is returned.

Sending your own module in for repair. This costs less, and your own unit is the core so nothing has to travel back afterwards. The trade is downtime: the module has to come off the truck before you order, and the truck sits for the whole round trip rather than for an afternoon. You can send your own Duramax ECM in for repair on its own page, and it lists the identical 25 units.

Three other routes exist and we do not offer any of them:

• A rebuilt exchange with a refundable core deposit. Cash is held on top of the unit price until the old core is inspected and accepted. We hold nothing up front.
• A new module from a dealer. It still needs programming after it is fitted, which means a dealer appointment on top of the part price.
• A used or salvage module. Nothing on it has been rebuilt or tested, and it still needs programming to your truck. Whatever cover comes with it comes from the seller rather than from a rebuild.

Erratic shifting points at the Allison module, not the ECM

Harsh or erratic shifting is a transmission control module symptom, not an engine control module one. Allison's own service bulletin lists harsh or erratic shifting, no forward ranges, stuck in range, will not start and no communication as symptoms of a failing transmission control module (`NHTSA-TSB:10058991`). That is a separate part, and it is not covered by anything on this page.

We repair Allison transmission control modules on the same trucks, as a send-in service only. The 5-speed Allison TCM covers 2001 to 2005 trucks, which overlaps the LB7 and LLY years here. The 6-speed Allison TCM covers 2005 to 2015 trucks and is matched on the Allison calibration code, A40, A46, A50 or T14A, rather than on the model year.

If the engine runs badly and the truck shifts badly, those can be two separate parts and two separate jobs.

How do I know it is the engine module and not a sensor I have already replaced?

Four patterns point at the module, not a sensor:

• The truck will not start.
• No communication with the module on a scan tool.
• Intermittent shutdowns, or a no-start after sitting.
• Codes that keep returning after the sensors were replaced.

GM has documented both DTC P2002 being disabled on L5P trucks, so a failed particulate filter goes undetected (`NHTSA-TSB:10156982`), and the module possibly not taking the right action when an exhaust gas temperature sensor disconnects (`NHTSA-TSB:10207699`).

Is it the engine module or the injector module that failed?

Every one of the 25 units on this page is an engine control module. No fuel injection control module is sold here, so if your diagnosis points at the FICM this is not the part you need. If you are not certain which module has failed, ask us before ordering rather than after.

Is this for the 6.6L Duramax or the 3.0L?

This page covers the 6.6L Duramax only, across all seven of its generations from the 2001 LB7 to the 2021 L5P. The 3.0L Duramax is a different engine and its modules are not sold on this page. Every option on this page reads "Duramax 6.6L" for that reason.

What do you need from me after I order, and where do I find my VIN?

Your VIN, nothing more. We reach out for it after purchase instead of collecting it at checkout. It is a 17-character number; the dash carries it, and so does your registration card. Programming starts when the VIN reaches us, so sending it promptly is what moves the order along.

My part number is not one of the options. Can you still help?

The 25 options on this page are what we stock for the 6.6L Duramax today. That list is what we carry rather than a statement about every Duramax module ever built, and the picker has no "not known" fallback to choose. If your number is not there, contact us with your VIN and the number off your module before you order.

Can I run a custom tune on this module?

These units are supplied as stock replacements carrying the manufacturer's current software. Reprogramming done by any other source voids the warranty, and there is no refund route for a part used for an engine swap or comparable performance work. If a tune is your plan, this is not the right unit to build it on.

How soon does it ship once I have ordered?

Processing and dispatch take 1 to 5 business days. The clock starts once your order is placed and your VIN reaches us, not at checkout, because the unit is programmed to your truck before it goes out. Getting the VIN to us fast is the single thing that shortens the wait.