I wouldn't replace them unless you think there is a problem. But if you do, you might as well get a fully loaded control arm with the front bushing, ball joint and rear bushing. The rear bushing is often torn. That's what is wrong with mine. I will just replace the rear bushing, but if I had to replace the front bushing as well, I'd get the whole control arm. Fred beans sells the fully loaded unit IIRC.