Front end clunk - '99 Expedition

I have a low mileage (40K) '99 Expedition E.B. that has developed an audible clunk coming from the left front suspension area. It occurs most often while making an abrupt right turn or hitting a bump in the road. No clunk if the road is smooth.
I've checked the ball joints, control arm bushings, wheel bearings, tie-rod ends, calipers, sway bar bushings and links. They all seem tight and secure.
Any ideas. Upper shock mount maybe?
TIA
Pete

I have a low mileage (40K) '99 Expedition E.B. that has developed an audible clunk coming from the left front suspension area. It occurs most often while making an abrupt right turn or hitting a bump in the road. No clunk if the road is smooth.
I've checked the ball joints, control arm bushings, wheel bearings, tie-rod ends, calipers, sway bar bushings and links. They all seem tight and secure.
Any ideas. Upper shock mount maybe?
TIA
Pete
I have the same model and had the same noises.I am pretty sure that if you check the link between the lower and upper suspension pieces you will find that the bolt has sheared.it may still be there and look ok, and even not move if you pull on it, but under tension it will move and then you will hear a clunk.it is real easy to replace.napa auto sells a front swaybar repair kit for about$30 that consists of 2 new links and the needed bushings.Replace them both and i bet the noises cease.you dont even need to jack the car up to replace them as long as youre fairly strong you can just shove em in with a rubber mallet to help