2001 Chevy Silverado four wheel drive transfer case

Just put new u-joints in front drive shaft and notice when I was putting drive shaft back into transfer case the the front yoke was lined up, tried to move drive shaft in transfer case and it wouldn't turn, it was trying to turn rear drive shaft, it's in 2 wheel drive, I ended up turning yoke on front axle, checked my dad's 08 chevy hia turns freely, checked by buddies o2 chevy his doesn't turn, I would think it should turn freely in 2 wheel drive, If it should do you have a idea what's wrong with mine, is it the electric shift motor, it sound like it working but not sure,
thanks john