4R100 Tranny Upgrade...Need a Program Change?

[cleatus12r]

So what you're saying is that you need the torque converter clutch to be commanded to apply at a lower accelerator pedal position in third gear. My guess is that it worked the same way before, but you never noticed it because you never took that trip before.

It's working correctly, just not in the manner that you intend to use it. It sounds to me like we need to play chip tag to remedy your situation.