Thanks for all the replies! I think that it is most likely the transfer case chain. I will drain the fluid and inspect next weekend. When I am driving and I let off the gas for a second or two and then step back on the gas there is a sort of clunk, like slack somewhere in the driveline. This is what leads me to believe that the culprit of the clicking noise is the transfer case chain. I will most likely be doing the work myself, as I don't trust any mechanics but one.. and they are only slightly cheaper than the stealership. I am pretty mechanically inclined and have the tools necessary, although I don't have a ton of experience with cars. But hey, there's always something new to learn!