I had this problem and it turned out to be the drop link rod on the off side. Once replaced problem was gone. After reading the advice on this site - that it may have been the shock mount - I did take the time to absolutely smother the nut at the top of the mount with grease - just in case it ever needs undoing!!!!!!! One point to note - the old drop link I took off was simple - one spanner and a 19 mm socket - however the new replacement was a pig - needed a multi-spline tool and a through socket to get them on - make sure you have these or another car if you do this yourself!! Other than that a simple fix - got genuine Ford part and it was only