Being a 2000 with my Ford experience Yea it's an alignment issue but probably due worn out suspension parts. These Expeditions are real susceptible to spindle bearing wear. which are modular by design meaning the bearing is part of the spindle. NOT CHEAP! A lot of weight on the front of these trucks. Of course there are ball joints and steering linkages. Could be a combination of things being 15 years old. Ray ASE Master Tech
Our next door neighbors had one of those and it just ATE front tires. He had a lot of parts replaced and even a top noptch alignment shop couldn't help him.
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