Driving down the canyon I noticed a slight tapping noise comming from the center of the dash. I cant find anything loose under the hood by the cowel. I did notice when I turned the air on, it got a little worse. I think there is something loose flapping from air, but what???
I had the same problem and mine went away after I checked the oil oe day. Later I was at the dealership and I asked what one of my friends trucks was there for andit was the same problem me and u r having. They said the dipstick wasnt all the way in and was making the tapping noise that sounds like it is nde the dash.