Hello, I have found that a 6L80 I have locks out 6th gear when output shaft goes above a certain speed. Changing the final drive ratio in the calibration will affect when other shifts happen but this downshift happens at a certain output shaft speed every time, regardless of what I calibrate VSS to indicate. This is swapped into a car with very low gearing so the car is not going that fast when it decides to downshift from 6th gear regardless of throttle position, and even using the scan tool to hold 6th gear won't prevent this downshift.
I'd love to hear if anyone knows about this problem and has a solution. TCM OS is 24256125 and calibration 24256124
Baldur