I hear on a regular basis, a clicking noise when I put the vehicle in drive and/or going to reverse. Doesn't matter if I'm on flat land or an incline. I'm having trouble getting it diagnosed because it seems every time I get to the dealership, it won't make that noise. They did something called a "Reset of the System". Did good for a few days and then it came back. I've had the truck since it was brand new.