04 2500 WT - Noisy 4x4 Gearbox
 

I have a 2004 2500 HD WT with 9,300 miles. I'm hearing noticeably loud gear noise coming from the area where my manual 4x4 shifter is located on the floor. Does not happen when truck is cold. At first, I thought I had noisy valves in my engine, but I soon zeroed in on the true source. Anyone else have this sound? Any way to dampen it?