Steve E, i have been reading the replies etc to anither lexus owner that seems to have or had the same problems,(may have been yourself) the symptons on that appear to be very simular to mine apart from the wet weather issues. Lexus are collecting the car tomorrow i will put this to them and get them to check it. Maybe they think that if there is no play in the ball joint then it's ok. Obviously this is not the case.
Anees, this has been suggested in the past by me to Lexus, the fact that it only makes these knocking noises in the dry would substantiate this, however the garage have informewd me that there are no bushes or leaking seals etc that they can find.??
one thing that i did not mention is that i put 4 new boots on 9 weeks ago and the front 2 are now just legal!!!!!!
many thanks guys i will update you if they resolve the problem or not. thanks for the welcome.