'00 WJ... 4 wheel drive not working!!! ???

[nvrstuk]

My pops has a 2000 GC with the quadradrive II. Tried to get up the driveway last snow storm, and found the front wheels do not spin at all. Shifted into 4 lo, and same thing. I crawled under to check the DL, and it spins at the same RPM's as the rear, but doesn't sping either front tire...... What is going on? Jeep has about 130k miles on it, and there are no noises.

I know there isnt a vacuum line or anything on the TC, the fluid is ok, and it cant be the viscous because the frond DL spins... right?

Any help would be great.
Thanks.