At the end of 2010 I replaces ONE ball joint at the end of a tension arm because I accidentally ripped the boot when trying to separate it with a pickle fork. I wish they had never invented those things - pickle forks, that is.
The other was not replaced at that time, so it may be the original after 135K miles.

I guess I'll mini-rant: My Suburban has 213K miles and has not had any front end pieces replaced, although it likely could use a new tie rod end. With the X5, which I bought at 84K miles, I've replaced the big tension rod bushings twice, one ball joint, and all of the rear subframe bushings. From what I've read on the Forum, that's minor...some have replaced everything rubber in both front and rear suspensions. I love the way the X drives, but IMHO the durability of suspension pieces, especially the rubber bonded to metal parts, leaves a lot to be desired.

Am going in next week to have my ex-indy (he works for a dealership now) find the oil leak that's causing my entire garage to smell like burned oil. That's another topic.