First off I'd like to say excellent forum! Can't find a thing for sportages anywhere else.

I'll cut to the chase:
As we were going up the driveway in 4hi (ice covered in compact snow)the car stalls and wheels lock. Take it out of 4wd and it moves normally. it appears the front diff has given up the ghost.
While messing about with it later it wouldn't let the transfer case disengage the front end as it seemed to be loaded up with torque. Car wouldn't move, even with transfer case in 2hi (front end locked solid, rear wheels spinning) and I had to be somewhere. Put it in 4lo and gave it a little pop with the clutch. Gggggrrind says the front end, take it out of 4wd and we're moving again.

I'm guessing it's something to do with the pinion/carrier as if I turn one cv the other turns the opposite way, and the front driveshaft is solid at the front diff flange.

I recently put in warn autolockers (hubs) when I replaced the 210,000km old front wheel bearings as i broke the vacuum hubs when I was removing them. Being that they were used on and off the last 5000km I don't believe this is my issue but I could very easily have done something wrong.

So, what I'm getting at is has anyone else had a similar experience? What sort of weirdness am I likely to experience when I finally go to remove this (quirky kia engineering or fairly straightforward)? and does anyone have one of these miata lsd they want to get rid of?