It's probably the water pump. It isn't usually the impeller that goes bad in car water pumps (unlike boat water pumps.) It's usually the bearings that fail, that's probably the squeaking you're hearing. This is usually accompanied by a slow leak out of the "weeping" hole in the water pump. When the bearings fail the slide instead of roll, this causes heat and that causes the seal to fail and that allows water to come out of the weeping hole as a tell tail that you need a new water pump.