Ball joint replacements, how do I tell if I need them?

[Rhodius]

I have a 2008 CX-9 Grand Touring currently at 119K miles. Just came back from the dealer who told me that it requires lower ball joint replacement, which including (if not mistaken) control arm will cost about $450-500, including labor close to $700. From 1-2 postings here, apparently this part broke quite often around this mileage. However I had two bad previous experiences with this dealer telling me one thing when it wasnt it (be that intentional or unintentional), so can someone tells me how do I tell if lower ball joints on the CX-9 needs replacement? FYI, adding oil and radiator fluid are about the extent of my mechanic ability. Dealer told me he logged a ticket with Mazda to see if that will persuade Mazda to do a TSB on this since he says this is a pretty common thing with CX-9. However seeing theres only a couple of postings here, not sure if this is a pretty common occurrences with CX-9.

Thanks beforehand.

 

[Scott91370]

Ball joints are almost always no fun to replace.
Jack up the corner of the vehicle and once the tire is off the ground try to move it top to bottom. There should be no movement.
Here is a decent video, but skip to the 2m 20s mark.
Ball Joint

 

[just_phil]

The ball joints can be replaced without replacing the control arms, but they need to be pressed out. I'd say there's hardly any savings in that, as the new control arm comes with new bushings too. I had my control arms replaced at 110k, as one of the ball joints was scary loose and the tire wear was out of control. Also, see this thread.

 

[Rhodius]

Thanks for your input. I took it to the tire shop where I had all 4 tires replaced last fall and alignment done. They said alignment looks good and no issue with the ball-joints. They also said there's a bit of play but has not become a safety and/or replacement issue. So then I went back and asked the dealer why they told me its a replacement and safety issue, the guy said according to PA inspection, which is up to anybody's interpretation, they think it's a safety issue. So anyway, I'm gonna drive it for another while. The tire shop tightened the nuts and rechecked the tire pressures, so if they were issues, hopefully this resolved that. I'll let you guys know.