The u1000 code (class 2 data link malfunction is still showing up in the transmission scan. and now it'* developed a new problem, I turn the ignition and it turns maybe a half revolution and starts clicking like the battery is dead. That started today.

did you have the battery load tested?

When I put my truck in 4 wheel drive it takes a couple try'* to engage and when I try to disengage it won't come out.
The 2 wheel light on the switch will flash, but nothing happens. Sometimes it takes a couple days for it to disengage. What could be the problem. I have replaced the switch and the actuator on the axel.