Sounds like you need a new CV joint to me. If you don't replace the CV joint it will get progressively worse. The classic sign of a bad CV joint is a CONSTANT "ticking" or as you say "clunking" as you drive. The sound may get louder or even decrease only as you turn corners.A bad CV joint can be potentially dangerous while driving since it is there to stablize each wheel. Each side has a CV joint. The worst case scenario is that without that stabilization, your wheel will eventually start to wobble and DISPLACE while driving. Not good. Dangerous.