Dash Noise Getting Louder w/ Speed - Help

[2001 TX Tahoe]

2001 Tahoe, just hit 200K miles a few weeks ago. One day I had a new noise which sounds like it's coming from behind the driver's side dash, kind of the instrument panel area and it hasn't gone away. It gets louder with speed (not RPMs) and isn't audible below 10 mph. It's kind of like a buzzing/whirring/grinding noise. It sounds mechanical. It does the same thing whether or not my A/C is turned on or turned off. All gauges appear to be working. A/C is working. Any ideas?
Thanks,
DC

 

[Grimes]

Have you or any mechanics taken apart the dash recently? I don't know of a fan there that would be clipping with your description. Only thing I can think of is that there is a loose screw or bolt, allowing room for parts to vibrate, which intensifies with speed as vibration felt from the road intensifies.

Personally I have a vibrating sound on the passenger side which must have started when I put the dash back together. My guess is that its the U shaped frame thing. Just sucks to go digging back there.

 

[2001 TX Tahoe]

Haven't had the dash apart recently. It's not a vibration from the road, but it's directly tied to speed.

I just tried a few things while driving while it was making the sound. Changed the A/C from off to on, hot to cold, dash vents to floor vents, recirculate on and off, and this didn't change anything. Shifting into Auto 4wd, 4H, and 2wd. No change. Then pulled the column shifter toward me as if to change gears and the tone of the noise changed and I could feel it in the shifter. I was able to downshift and upshift, but each time I could feel a slight vibration in the shifter and the tone would slightly change when I shifted gears. Ideas??

 

[Xypher]

My wife's 02 Tahoe does the same thing. I found it to be something behind the panel in front of my left knee when driving. I don't know what it is, but pushing ******* that panel when it's being noisy makes it stop. Maybe give that a try to at least narrow down your options a little more.

 

[2001 TX Tahoe]

Oddly enough, it ended up being my parking brake cable touching the driveshaft. The sound was amplified up through the dash.