Seized T-Case

[SeanCollins]

so I got the car up on the lift and noticed instantly that when I spin the rear wheels they do not spin together but when i spin the front 2 they are spinning together. What could cause this? I am in the process of getting the transfer case back off after finding out the last one i installed may be the incorrect spline count, but found that to be a little odd as I recall spinning all of them together

 

[97gst_spyder]

The tires left to right will spin in opposite directions. This is how diff's work. Is the t-case installed?