98 K1500 manual trans--no 4x4

[Bryan59EC]

Some time ago--two years maybe, I had to replace the transfer case on my pickup.

All was good until about 2 months ago when I needed the 4x4 it did not work.

Changed the actuator and it worked just fine----once

Fast forward to today -- again---no 4x4 engagement

Fuse good----cannot hear actuator with key on and going thru the ranges

Change TC switch---no change

plug wiring into removed switch and the actuator engages (I think)

Remove actuator plug harness to actuator key on
depress TC switch and actuator retracts----release and the actuator extends.

replace actuator----plug TC into loose switch actuator makes noise.
Start truck put into 4-lo and go out to my yard to try to climb a some sand.

Bury the truck-----the ranges seem to be working but I really have no way
of seeing if the transfer case is actually engaging the front driveshaft.

Is it possible that some shifting mechanism has broken inside the TC.

Sticking my finger inside the TC switch hole, it feels like the pawl is a bit off center----I did not think to see if it actually moved out of the way when in 4wd.

Or did something wig out in the differential---not sure.

Any ideas???