grinding noise when diff lock switch is disengaged and truck will not move

[azfj80pinal]

I have done some research on prior posts however the description of failure is opposite of what I'm experiencing. All of the post that I've read said that there was a grinding noise when the center diff lock switch was engaged . My grinding noise I experience when the diff lock switch is disengaged after I disengage the truck it will not move. I was trying to get a good idea of what I should be ordering due to the fact that this is a daily driver and I would not be able to take it apart and leave it down for an extended period while I order parts. Any opinions and insight would be greatly appreciated.

 

[retrofive]

Drive flange?

 

[Tools R Us]

Drive flange?

^^^ This is the first thing to check. Have a helper hold the brakes and shift drive, listen at each front hub. On the one where the most noise is heard, remove the center cap on the drive flange, repeat above and will see the axle/birf shaft spinning in the drive plate.

The early rigs have shorter splines, so more commonly strip. It can be driven with the CDL locked.