lockup

I've searched and searched and can't find a thread that remotely answers this. I've driven dad's 2000 Explorer and it doesn't seem to do this and he does absolutely nothing to maintain his vehicle. So here goes: 4r44e Trans. It takes at LEAST a half mile of steady 60 mph before the torque...

Hello! I really need help! I changed my old 4R55E wich broke a band to a 5R55E from a 1997 Explorer. The tranny was just rebuild. Lockup failed to engage immediatly when I took the car for a test drive. What happens is that when I pass a certain speed (80km/h) lockup should engage but instead...