it seems to happen when digging into a load and I had to use the 4x4 to keep from slipping and spining the rear tires. Sorry, I haven't figured out the quote function.
ualjack, I'm trying to understand what you were doing. You were digging into a load and the rear tires were slipping, so you put it into 4x4 for extra traction. Were you lifting with the loader at the same time you were trying to go forward? That's what a loader is for and we all do it. This would push the front tires down hard giving them extra traction while the rear tires were already slipping. Maybe this is puting to much of the forward motion force on the front axle being that the rear tires are slipping and the front tires are biting in hard. Just a thought. The front tires and axle are doing all or most of the work. You would like to think that the front gears where made strong enough to take this being that is the way a loader is commonly used. You push into a pile and lift at the same time.
I hope you just had a set of gears that weren't set up right and they gave out from abnormal wear. Years ago, I worked in an auto/truck garage and was very careful setting up differentials to their proper tolerances, otherwise you can ruin a ring and pinion quickly.
Please let us know what they think the cause was. I would hate to destroy the front gears in my CK30hst by pushing into a pile and lifting but then, how else do you do it!!!