You need a 07-08 TCM flashed with a 4L60E OS. Then flash the ECM with a tune from a 4 speed vehicle. Manual and 6 speed tunes will not work.
Doing that will make the ECM and TCM talk to each other,...
Type: Posts; User: Montecarlodrag
You need a 07-08 TCM flashed with a 4L60E OS. Then flash the ECM with a tune from a 4 speed vehicle. Manual and 6 speed tunes will not work.
Doing that will make the ECM and TCM talk to each other,...