Lower & Upper Ball Joint
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2004 Ford Pickup, 2004 Ford Excursion, 2004 Ford Cab & Chassis, 2003 Ford Pickup, and 2003 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.
Raise and support vehicle under axle. Move lower edge of tire in and out while watching lower steering knuckle arm and lower part of axle jaw. See Fig 1. If movement exceeds 1/32" (.8 mm), replace lower ball joint. To check upper ball joint, move upper edge of tire in and out. See Fig 2. If movement between upper steering knuckle arm and upper axle exceeds 1/32" (.8 mm), replace upper ball joint.