Grinding in 4x4?

[Nappeal]

We got about a foot of snow here in town last night, so I put my '92 in 4 wheel this morning, and it drove fine. After work, drove fine until I got to the drug store & got stuck in a spot, so I put it into 4x4 (w truck still running), got out of the spot, & turned off 4x4 (w truck still running). As soon as I got to the dry pavement of course, a low but repetitive grinding noise progressed so much within a mile that it became loud & constant, esp when turning. Also heard a "winding down" noise when coming to a stop, so twice I pulled off, shut down the engine for about 30 sec & restarted just to find no difference. Finally pulled into a gas station & let it sit while trying to think of what to do. 20 min later, I drove around the station & no problems...decided to drive home & it was driving fine again. I know my brakes need replacing but this seems like a 4x4 problem. I've put a lot of $$$ into this thing in the last couple years & can't afford to take it in @ the moment, so I'd love to get some imput!

 

[Roadrunner777]

Current behavior in 2x4 and 4x4?

 

[Albino 94LTD]

When you turned off the 4x4, did you back up a car length to disengage the auto hubs? (unless you have manual hubs then it's a different issue) as per the owners manual?