Transfer case? "Growl"

[97Yukon]

Hello.

 

This is my first post.

 

I own a dead stock 97 Yukon SLT 4 door with 130,000 kms on it.

 

I have what's best described as a "growl" (almost sounds like bearing noise) at all speeds, in all gears. You can even "feel" it at times through the steering wheel, seat, etc.

 

Here's the odd part. It happens in 2Hi. If I push the 4Hi button, the noise disappears immediately. When I put it back in 2Hi, the noise slowly returns.

 

Everything else with the truck is great.

 

Thanks for any insight.

[quackmaster]

my guess is the rear pinion bearing