My 2012 Colorado Z71 4x4 with the 5.3 makes a noise sounding like it's in the left rear as if a rock was thrown at the side of the bed. It only does this after starting it and driving a few hundred feet. It makes the noise once and that's it until you shut the truck off and start driving again. It's does this everytime I drive it. Can sound like a rock coming out of the tire and hitting the wheel well. Have no idea what it is. I have not asked the dealership yet.

 

at least its under warranty. post the final fix.

 

z71black2012,
Keep us posted on what you hear from the dealership, and we're available to follow up on your appointment if need be.

Sarah (Assisting Louis), Chevrolet Customer Service