well it could be a couple things, Ball joints, would be my first guess. I am also having a bad noise froom the front of my 2000. Im pretty sure i have it narrowed to the front differential has gone bad...not a cheap fix...$2500 for just the part from the dealer. thank GOD i can do the labor myself.
for the one that said it makes the noise around turns...if its 4x4 it verry well could be your 1/2 shaft (cv shaft) which is your drive shaft that comes out of your front diff.