Need feedback from owners of Silverado PU's, 2011 and up.

I have owned several, my current one being a 2013 Black Diamond edition Avalanche 4WD. My current rig gets 19 on a road trip and 17 around town. 5.2 engine. I drive it hard and fast and this is my 2nd avalanche, they are essentially a Silverado. I wrung my last one completely out as a work rig at 160,000 miles. I don't think you can do much to improve the mileage but 2 WD may get better mileage.