tire spin

[Coalsmoke]

Well the great white stuff has arrived for the season and I had the oppotunity to pull out anOlds from the ditch (apparently he didn't notice that the ground was covered in snow and ice ) So, he hooked the tow strap on his end (I let them do the hooking if they are capable, so that if something breaks, they can't point fingers at anyone but themselves) and give a try in 2wd, I feel the LSD give a little chatter and I know it is locked up, but still no go so in goes 4 lo, I get the ominous clunk - clunk, and the front hubs are locked. Even with all four tires spinning, I barely got him out (his rear tires were well off the ground and his front-end was wedged in the ditch, andarently those older cars are heavy). Anyways, like I said, all 4 tires were apparently spinning, but my front dif is open? How does that work?