Expedition would shudder (like the abs was kicking on) while stopping every time at the start of every drive until the abs light would come on. At that point it would brake fine. Thought maybe the wheel sensor was bad (which my husband could replace himself) but we took it in to our mechanic and turned out to the the wheel hub assembly. Mechanic said it was wobbling so bad he wouldn't recommend driving it at all. Coughed up the money and had it replaced.