Hello, I need help. I've killed my car, it's stuck in the driveway.

It is a 2008 Chevy Suburban, with the L76 6.0 Liter, and a 4L-70E transmission. There is a T42.

I read the calibration with no issue, and no errors. I made some mods, tried to reflash, and I am getting

11:19:15.458: Erasing TCM flash memory... (please wait up to 45 seconds)
11:19:16.099: TCM flash memory erased OK
11:19:16.359: Reflashing TCM's memory...
11:19:40.694: Total time: 00:24
11:19:40.694: Data compression achieved: 0.0%
11:19:40.894: Checksum of flash failed after write completed. Please reflash the controller.
11:19:40.904: TCM is in an unknown state.


So, I searched around here, didn't find much. I reattempted to read the TCM, which it did (saying there were checksum errors). I recomputed the checksums and tried to reflash, I got the same errors.

The TCM is definately dead, I get continual "Service Traction Control" and "Service Stabilitrak", and shifting to a gear shows no gear selected on the dash and barely any movement of the vehicle.

The tunes are available at:

http://www.nac.net/photos/efi/t42%20tunes.zip

(both stock that I extracted and the mods I am trying to reflash).

Any help appreciated, desperately need this vehicle to be running ASAP.