Ball Joint: Testing and Inspection

Ball joints must be replaced if any looseness is detected in the joint or the ball joint seal is cut.

To inspect ball joints, raise front of vehicle allowing front suspension to hang free. Grasp the tire at top and bottom and move top of tire in an in-and-out motion. Observe for any horizontal movement of the knuckle relative to the control arm.

If the ball stud is disconnected from the knuckle and any looseness is detected, or if the ball stud can be twisted in its socket using finger pressure, replace the ball joint.

Ball stud tightness in knuckle boss should also be checked when inspecting the ball joint. This may be done by shaking the wheel and feeling for movement of the stud end or castellated nut at the knuckle boss. Checking the fastener torque at the castellated nut is an alternative method of inspecting for wear. A loose nut can indicate a bent stud or an "opened-up" hole in the knuckle boss. Worn or damaged ball joints and knuckles must be replaced.