Rear tires in a turn

I've noticed in the last couple days that when I maneuver a turn ie. a tight left turn, I can hear my rear left tire bark a little on the road (when in 2 wheel drive). Seems like it wants to turn faster than the other tire is going.

It has been really snowy and cold lately and I've used both the auto 4x4 and the 4x4 hi. I haven't notice any problem using them and Haven't had to pull anything out of a snow pile. I haven't heard any strange noises or anything that would have raised suspicions. I just noticed that the tired "skids" a little as I turn sharper. It's hard to tell if it does it to the right as well. I can't hear it easily and its hard to tell with the icy bumpy roads if it is doing the same. I'm about 60% that it is though. I just had the spider gear replaced a couple years ago. I haven't had any problems till now.

Could be the Eaton locking rear is engaged, shouldn't be, if you have this option, the only way see to what's what is jack it up and spin the rear wheels by hand, also make sure the 4wd is disengaging.

Once I jack up the read and spin the tires what will I be looking for?

First see if your option list, in glove box usually lists, G80 which is a locking diff, if so both wheels should turn in opposite directions from each other not in the same direction. Truck must be in neutral brake of of course, be safe here, block the front wheels.

Pretty sure it has it. I noticed the wheels turning opposite when I had it jacked up the last time. Am I checking to see if they still go in opposite directions?