I just replaced the vacuum lines that control the vacuum actuator, and the vacuum actuator works. The transfer case shifts into gear as well. The cable going to the axle barely moves, and the axle does not lock. I even lifted a wheel off the ground to rotate it while trying to manually engage the axle, but it does not move enough to spline. Does this mean I need to take the axle out and rebuild it?

 

Have you disconnected the cable from the axle to make sure the cable itself is not stuck?

 

Good time for a bravada passenger side axle upgrade. Get rid of all that vacuum at the axle. The actuator and the 2 piece shaft. No this does not make your truck awd or create binding in the front end.

 

Sure, it doesn't create binding, but the transfer case will get more wear on it.

 

the cable does move slightly, and I had someone listen for anything moving in the axle,, and we can hear the collar move and hit the shaft, but it feels like the shaft on the inside itself is not spinning.
To disconnect the line to check it, do I unbolt the 3 bolt housing, or do I spin off the nut on the cable?

 

if that’s what you think and your reason for not doing it. That’s fine. It’s your truck.
you must not realize your t case is always running every time tour truck moves. So does the front axle. Yes it free spins all the time. Just giving you an idea to eliminate the Issues you have. Noting more nothing less. It’s your choice on what to do.

 

The diff grenade itself. I know it wasn't me as well, as I got the thing a few months ago. I have a new axle on the way. 👍