Ok i'll try to break this down nicely for everyone.

- Its a AWD Axle
- I reciently removed/replaced the whole front diff in order to drop the oil pan
- Its cold as hell lately (~10-30* averages) and it sits outside

Ok now to the noise.
Its speed dependent, but totally independent of the engine so its nothing engine related. Its like a low frequency grumble and i can actually feel it through the floor pan. The amplitude of the sound increases with increased throttle input and is almost non-existant when coasting. I figure its one of the gears in the front diff, and i plan on checking the axle lub level but wanted to get some other opinions.

Everytime something acts up on my vehicle i want to ...

 

Bah after a little more poking around i'm pretty sure its my Transfer Case going "Game Over Man!" Oh well its been clunking for about 20,000 miles so it finally died...