Hi guys, I searched for this problem and can't seem to find it and/or solution for it:

I went off-roading, engaged the 4Low Lock. After we were done and got back on the paved road, I put it into Neutral, pressed 4High (unlocked), heard the switch of the Transfer Case, light indicator stopped flashing and indicated it was in 4High (unlocked) but felt the car driving as if in 4High Locked. Stopped and slowly took a hard turn and surely it was locked up. Eventually got it unlocked by messing with the controls and backing up and doing all sorts of maneuvers and drove home....

Now it is locked again... What I checked:

- took off Aftermarket T/Case Motor, made sure it rotated in each position
- made sure T/Case shaft was rotating into various positions.

I then took off the Front Drive Shaft so I can drive it in 4High Locked, AND IF F***ing unlocks in the middle of the road and for some reason couldn't lock back up!!! I had to reinstall the F.Shaft on the side of the road...

I then:
- Lifted the tires off the ground and was able to switch into each T/Case gear and was able to get it into 4High (unlocked).
- Started driving and still in 4High (unlocked), it locked up again.

Is it possible the Aftermarket T/Case Motor is not rotating to the correct positions? (it is meant for this car... :-/ )

please help...

 

Someone else had a similar issue and it was the fork in the transfer. His would happen going down the road.

 

Meaning I got to take apart my T/Case and rebuild it?

 

Yep. Have to pull and separate the case to get to the fork. Several write ups on the process.

 

The hardest part is clocking the t case enough to remove it and reinstall it.
While you are inside the t case put a new filter in it.

 

Year and model, year and model, year and model, miles on the clock, would be helpful.

Then we could tell you if you had a plastic T Case Hi/Lo shift fork, or the updated metal fork, and we would know which T Case you have.

 

3.5 hours of work, Fixed and works like a charm! Also rotated the tires because driving with a Locked T/Case for a week tore up the front tires :/

Took off the T/Case off, took it apart and replaced the Shift fork.
Did not have a new filter (Chevy Dealer didn't even have one..?) but thankfully the one in there was in decent condition so I just cleaned it and reinstalled it.
re-sealed, new gasket, filled oil.

See these videos, Super helpful!:

 

Parts I bought: