Results 1 to 2 of 2

Thread: T76 Transmission / Tuning Swap - I'm stuck!

  1. #1
    Junior Member
    Join Date
    May 2008
    Posts
    15

    Question T76 Transmission / Tuning Swap - I'm stuck!

    We are working on a unique project in which we have replaced the factory transmission in a 2010 GMC Terrain ("Generation 1" 6T40 with a T76 Controller) with a newer, 2012 6T40 Transmission which is a "Generation 2" with a newer T76 TCM. The "Generation 2" Transmission & TCM was purchased brand new from a dealer, and as such I don't think has a flash of any type. The Gen-2 trans & TCM has been installed into the 2010 vehicle and it doesn't have any forward gears and it give codes which indicate TCM communication issues from transmission "Control Module Not Programmed" in the TCM. I interpret this as the factory not supplying a calibration file of any type to the transmission, expecting that a brand-new transmission & TCM would be flashed by the dealer after installation. I'm not sure if that is an option as this is a newer 6T40 designed for a 2012 vehicle that's installed in a 2010 Terrain.

    I've pulled the tun from the Gen-2 TCM now that it has been installed into the vehicle, and the information from it is as follows:

    VIN: N/A
    Hardware: 24255544
    Operating System: 24265790
    Calibration: 24265789
    BCC: 5789
    Transmission Calibration: 24265791
    Transmission Diagnostics: 24265792
    System: 24265793

    Do I need to find a "full flash" for this TCM, or just a calibration file? It appears that EFI-live doesn't support full-flashing of T76 controllers (yet, I hope). I believe it does supporty calibration-only flashes (via V8). I did try to flash a calibration file from a 2012 Terrain but EFi-live give me an error from the operating systems not matching. Any ideas? Would it be possible for a dealership to flash the TCM using a VIN from a 2012 Terrain via a Tech-2? I'm lost right now!

    Thanks,
    Josh

  2. #2
    Lifetime Member GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    13,148

    Default

    All new ECM's or TCM's have what I guess could be called 'no start' programs in them. So yes they need to be flashed with a TechII, all you need to do is tell SPS (GM's programming software) a VIN from a 2012 Terrain and it will flash in the correct tune.
    I no longer monitor the forum, please either post your question or create a support ticket.

Similar Threads

  1. T76 TCM tuning support added
    By GMPX in forum 6 speed/8 speed RWD/FWD Transmission Tuning (incl T43, T76, T87)
    Replies: 22
    Last Post: April 10th, 2015, 05:49 PM
  2. Cruze, Sonic, Regal T76 TCM Tuning time
    By GMPX in forum E39, E80, E82 & E92 SIDI ECM's
    Replies: 12
    Last Post: June 10th, 2012, 09:41 AM
  3. T76 TCM Tuning testers needed
    By GMPX in forum 6 speed/8 speed RWD/FWD Transmission Tuning (incl T43, T76, T87)
    Replies: 4
    Last Post: May 6th, 2012, 10:31 AM
  4. transmission swap
    By autohouse in forum Tutorials
    Replies: 1
    Last Post: October 3rd, 2011, 02:48 PM
  5. 4l80e swap stuck in 2nd
    By 4wheelin in forum 4speed RWD/FWD Transmission Tuning (incl T42)
    Replies: 14
    Last Post: January 22nd, 2008, 12:16 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •