It sounds to me like something is rattling against one of the pulleys. Pop the hood and see if you can see anything resting against any of the pulleys. (Engine off). IF you can't see anything, start it up and look, keeping your hands outside the engine compartment. If you do see something, see if it will move and stay. If not move it and restrain it by tying or something.
There's also the possibility that it's your water pump. Or a bearing in the A/C, power steering, or alternator. Without knowing and being able to see and hear it myself, I can't give an honest opinion of whether you can drive it 6 hours.
Has it had all the regularly scheduled maintenance such as belts, hoses, etc?
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Monday, May 11th, 2015 AT 11:00 AM