Does anyone know of a method to test for worn ball-joints? My car is getting up there in miles (80K) and I would like to rule them out as a cause of a vibration problem I'm having.

Also, if they do need to be replaced, can just the ball-joint itself be replaced? My service manual says the entire control arm needs to be replaced in order to change-out the ball-joint or control-arm bushings. I would like to do botth. Thanks in advance.

I've seen mechanics(when I had a car with a worn ball joint/*)take a large/long metal bar[with the car up on a lift,and the wheels/suspension fully exrtended downward],wedge one end somewhere on the car'* frame(not exactly sure where,probably different place on each particular car),or on a portion of the lift frame itself [as a fulcrum],and put a few quick,hard, upward thrusts on the ball joint, letting the suspension return to it'* original position after each thrust,............it shouldn't have ANY play/slopiness in it,nor should it make ANY kind of 'chucking' noise..........

Put the car up a few inches on solid jackstands. Then I use my jack handle (4 ft long and strong) to pry off the floor up to the tire feeling for looseness or play.

If the joints are super bad jack car up and putting your hands at 12 and 6 try to wiggle up and down, any play will typically be a ball joint.