Loud Humming Noise

A loud humming noise has recently appeared when I turn my truck on. It seems to go away when I let out the clutch to go into gear and start driving. Reving the engine seems to make it go away for a second but then come back. I'm about to head to Alaska and want to know if it's somthing I need to deal with before I drive a couple thousand miles. Thanks.

Its most likely just something loose that is vibrating. Kind of hard to say without more info or being there.

Loud humming, especially from the front , could be wheel bearings, have them checked.

If it relates to the clutch operation, bad throw-out bearing?BJ