fourwd1: Seemed to me like one wheel had better traction than the other(one side was on packed snow, the other was on smooth ice, ice skating rink style :-P ).

As far as the oil in the differential, The bottle used to fill it says in very plain language that it is for limited slip differentials. In fact, it was purchased at a GM dealership(the axle is for a Chevy 3/4 ton diesel). Though there are no guarantees that the stealership wouldn't lead a customer astray, I'm reasonably certain it is the right stuff.

Thanks for the help, everyone.

My '86 4Runner went to the bone-yard November 29, 2004 at 10am after roughly 430,000 miles on the original engine and transmission. :-( Looking for something else to wheel in...