np231 popping/slipping

The problem happens when I hit the gas in 4 hi on ice. There’s a loud popping/clunking sound. It only does it in 4 hi and doesn't do it when cruising or when accelerating lightly. Thought I broke a spider gear or side gear in my front axle but that wasn't it. The sound also happens really bad when turning on pavement in 4 hi (which I know I shouldn't do), in fact I think this is what caused the problem when I did a 360 on ice into an intersection and had to get out of the way fast and didn't have a choice. It's the Np231 t-case. I think the problem is with the main shaft sprocket and/or the front output shaft sprocket and drive chain being shot. Anyone else think this is the case? If so, would it be worth it to replace the parts or would it just be better to get a low mileage t-case from a junkyard?

Sounds like a stretched chain, but I would check the ujoints to be certain. If you have broken output shafts/teeth, your going to have to tear into it anyways. If this is your daily driver, I would look for a junkyard tcase and swap them out until you can rebuild that one, if it is bad at all.