4L80E in a 2008 GMC sierra...

[boostadik]

I fried my 4L60E. Have a 4L80E coming. I understand that my truck has a separate TCM that controls the transmission. Support at HP tuners informs me that I need to have the TCM flashed with the Tech2. My question is that what exactly do they need to do? I went to the local dealership and they said that I was speaking chinese. If possible could someone explain the process of flashing the TCM with the tech2. Is this the only way to calibrate/run the 4L80E in my truck? What other information/steps do I need to do? I have read tons of posts on older style PCM/TCM calibrations, just not really and tech articles out there for the newer trucks.

VCM OS ID: 12617631
TCM OS ID: 24239927

Any help would be appreciated....

Thanks!

[flame]

The dealer system likely won't allow it because it goes by your VIN. You need to find a VIN with the options you need and have them reflash to that. They may have to tell it that it is a new module even though it is not so that it does a full write. You will need to rewire for the 4L80E but I'm sure you already knew that.

[boostadik]

Not really understanding the whole VIN part. So, find a 2008 truck with a 4L80 installed and give that VIN to the tech that is flashing the TCM? Just a little confused...

[boostadik]

Would it just be better to get a 08 4L80E TCM to reflash?

[flame]

The module is the same just the programming is diff. Yes you need to find a truck with the 4L80E trans and use that VIN. Not sure if they have to do the engine controller too to keep the OS talking to each other.

[daniel6718]

its simple as.adaptor harness, problem is the iss, anyone know how to make it work?

[flame]

its simple as.adaptor harness, problem is the iss, anyone know how to make it work?

If you are using the 4L60E pcm and using relays to reverse the logic of the one shift solenoid then you do not use the input speed sensor.

If you are using a 4L80E pcm then you will need to add the wires in for the input speed sensor to the pcm.

[Shrek]

From the original post, this truck is a 2008 model. It would have an E38 ECM and a T42 TCM. The original 4L65 had an ISS - it has a different connector than the 4L80.

The TCM or transmission connector plug can be repinned for use with a 4L80. The T42 can be programmed for either a 4L65 or 4L80.

The system segment in the E38 ECM is different between 4L65 and 4L80 applications.

Most straight forward approach is the reprogram the E38 / T42 with a 2008 year matched calibration (ECM & TCM) that used a 4L80.

[IDRIVEAG8GT]

The T42 to a Sierra requires a 4L80E file from a van to be flashed into it. Call the guys at PCM For Less, they know what I'm talking about.

[scooter k]

I'm using PCMforless adapter harness and trans tune. My truck is a 2008 and requires EFI live for intial program. Couple codes can't be tuned out using HPT.

[IDRIVEAG8GT]

^ which codes?