When I'm turning backwards or forwards it want to jerk and jump really bad. ????

I sure will. I was told that it could be a rear wheel sensor. Could that be? It's like when I turn the wheels are turning at different times.

When you turn the wheels, they will turn at different speeds. If the speed sensor is bad, the ABS pump will activate recognizing the wheel wasn't turning, but that should happen all the time the car is moving. A wheel bearing could also be a cause. Have it inspected to be sure. Another comment is to have the rear differential oil inspected for the limited slip function.

Almost sounds like the 4wd model's with 4x4 active while turning on dry pavement. This is awd i think. But it is GM.

That's what I thought but I have the button off. It's something in the rear end. Like I said when I turn it jumps real hard. Jumping over and over until I straighten out. That's forwards and backwards