Jack the front up under the control arm, then get a big pry bar under the tire, and have someone work the tire up and down. If you see play in the joints - replace them. If they squeek, replace them. If no play in the joints, and no squeek in the joints, then keep moving things until you find the squeek, the replace that part.
I know, it sucks. But I think just about all cars, on average, have worn suspension parts by the time they hit 100k. At least the MLs let you know with an audible warning!
