Chris, if you push down on the front end and if you are sitting in the car and turn the wheel you hear the sound, it is hard to trace the exact location but is most likely the ball joint on the lower control arm. I had mine replaced but as my wife is a nurse i tried injecting a little wd40 into the rubber ball joint to see what the score was (not recomended but as the car was booked in for the replacement i thought i'd try it) Hey presto the entire noise had dissappeared. I wouldn't use this as a fix as there must be evidence of wear around the joint in the first place ( slight vibration around 70MPH?.)
Hope this helps.
By the way have a look regarding the supplier on the front page of this site. Don't try a cheap supplier as it's a waste of time and money. I paid £380 for the 2 in the end and am very happy with the improvement and removal of the terrible noise!!
Regards
steve
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