99 Sierra 4 Wheel wont disengage.

[eclivic]

I have a 99 Sierra with Pull Shift 4 Wheel Drive not Button so I cant seem to find any help searching this or any other forums. I blew a Tranny line 3 weeks ago so I am swapping in a rebuilt tranny and I figured since I will be under there maybe I can fix the 4x4 issue.

 

Basically what happens is  if I go into 4 High and then go to 2 High, The 4x4 light shuts off but it doesn't disengage. When you drive say 100 feet or so something slams and it finally disengages. I have read a bunch of stuff but cant seem to get any help because everything I read say push this button and that button but I don't have buttons, I have a stick that I pull back and forth.

 

If im in 4 High then switch to 2 High and go into reverse about 5 feet it will disengage but that does me no good if im driving on a busy street and need to get out of 4 High.

[davester]

Well, with a manual shift TC, and the overall 4wd system working correctly, when you physically moving the lever from 4hi to 2hi, the transfer case is immediately out of 4wd mode (so, even though the front axle is still locked, no power is being transmitted to the front axle from the transfer case).  Then, a second or two later, the actuator in the front axle disengages the locking gear, and you are completely in 2wd mode.

 

If, when you shift the lever from 4hi to 2hi, and the TC remained in 4wd mode, then there's a problem with the transfer case, from the lever on the outside of the case not being properly bolted on and is now worn, to the mode fork being really worn to other bits inside the TC being worn/damaged.