I have. 2011 Sierra 1500. This happened twice today. Parked in my driveway came back to find it had rolled back. Thought I was losing my mind. I pulled it back up and set the emergency brake. Checked 2 hours later and it had rolled back again. This time I have sand bags behind the wheel. Guess I'm heading to the dealer in the am. Assuming no one has heard of a fix?