88b2 front end problems. Help!

[B2crawler]

Have an "88 bronco 2 with d28 front. When I turn the front driveshaft I can feel it catch and when you keep turning it to make wheels spin it breaks loose right as wheels start to spin and just turns and catches again and slips again. Any answer as to what this might be? I took front third member off to see if it was the ring and pinion but they appeared to be fine. I am stumped and don't know what it is. Could I have missed something when looking at the gears or what? Any help as to what this might be will be greatly appreciated.

 

[4x4junkie]

Auto hubs? If so, check those.