[curtis73]

All you can inspect about ball joints is the grease fitting and the nut on the end. The business end of a ball joint is concealed completely.

Also, a ball joint breaking is almost never something you hear about. Ball joints get loose, but two huge symptoms typically show up first; 1) noise, and 2) rather extremely noticable handling characteristics. A ball joint breaking is either a sign of a very faulty joint, or incredibly excessive wear. In the case of the faulty joint, the blame lies with the manufacturer and if its under warranty you have something to go on. If its the second case, the blame lies with the driver for not keeping maintenance up to date on his/her vehicle. Ball joint wear can be tested with a pry bar, but a breaking ball joint is not something you can predict any more than you can predict a stone on your windshield.

Its unfortunate, but there is absolutely no way (except metallurgically examining a ball joint under an electron-microscope) to predict a broken ball joint. Its just not something you can test for.

The other unfortunate part of this is the subjectivity of whether or not your tie rods need to be replaced. When you take your car in for service and someone inspects the tie rod ends, the answer you get (politically correct or not) is based on several things. Service techs will "upsell" things when they can, but the extent to which they do that depends directly on the desperation they're willing to reach, and the gullibility of the customer. A financially stable honest tech will give you the straight dope. An unscrupulous tech who needs to make rent might try to sell you new tie rods.