Operation CHARM: Car repair manuals for everyone.

Ball Stud and Knuckle Inspection - Front Suspension

Replace the ball joints if any looseness is detected in the joint or the ball joint seal is cut.

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





Replace the ball joint if the following conditions exist:
1. If the ball stud (1) is disconnected from the steering knuckle and any looseness is detected
2. If the ball stud (1) can be twisted in the socket using finger pressure

Also inspect the ball stud tightness in the steering knuckle boss 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 castellated nut fastener tightening specification 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. Replace worn or damaged ball joints and knuckles.