rear diff question

[hiridn69gmc]

The other day I was sitting at a friends house and we were wondering if my truck had a limited slip.

Well the easiest way, lay some rubber.

He was on the drivers side of the truck when I stomped on it and sure enough the tire spun, cool I thought.

So I took off and looked behind me, only one trail

Now my question is, were there ever and open diffs where the left side took the power? I have never seen and it was pretty funny. But if it isn't supposed to do that, it needs fixing. More to add to the list.

Thanks