Driveshaft Stuck

I have a 2000 4x4 Suburban with 170k miles on it. I started experiencing some really bad vibration and have isolated the problem to be the rear u jount on the fwd driveshaft. Pretty simple job in general but I have a problem getting the driveshaft out. I have the rear of the truck on jackstands and in neutral. I've removed the straps on the fwd u joint and I can't budge it back into the transfer case so I can drop it down in the front. When I pry backwards on the driveshaft, it moves but so does the transfer case almost like it's one piece. Any other ideas would be appreciated greatly.

I have a 2000 4x4 Suburban with 170k miles on it. I started experiencing some really bad vibration and have isolated the problem to be the rear u jount on the fwd driveshaft. Pretty simple job in general but I have a problem getting the driveshaft out. I have the rear of the truck on jackstands and in neutral. I've removed the straps on the fwd u joint and I can't budge it back into the transfer case so I can drop it down in the front. When I pry backwards on the driveshaft, it moves but so does the transfer case almost like it's one piece. Any other ideas would be appreciated greatly.

Slip joint froze up.
Can you greese slip joint?