Brakes

Fairly common issue on GM vehicles is rust forming between the wheel speed sensor and the hub. This usually causes the ABS to apply when stopping.
Your issue sounds different than that because you say it happens when you turn corners without the brake on. In this case I think it is more likely to be a bad wheel hub bearing assembly.

Jack up the front end and spin the tires by hand and listen for noise and try moving the tire by rocking it in both directions looking for play.