Place The Pork Tenderloin In A Slow Cooker; Pour The Root Beer Over The Meat. Cover And Cook On Low Until Well Cooked And The Pork Shreds Easily, 6 To 7 Hours. Note: The Actual Length Of Time May Vary According To Individual Slow Cooker. Drain Well. Stir In Barbecue Sauce. Serve Over Hamburger Buns.