I've got a loud clunk noise coming from my front suspension. I've been trying to find it but I just can't figure out where its coming from.

It usually happens when I'm pulling out of my drive way and the front tire pops down the curb. I can also make it happen if I drive in reverse and step on the brakes hard. So basically it seems to happen when I unload the front suspension.

Ive looked everything over to make sure all the bolts are tight and so forth and I just can't find anything wrong. Its driving me crazy.

My front suspension has the following mods:
Koni SA shocks with Ground Control adjustable spring perches.
1Le swaybar w/ poly bushings/endlinks

One thing to note about the front springs is that the kit uses a smaller diameter spring than stock so it puts the weight on the top mount differently than stock.

Anyway, I know its a long shot, but does anyone have any ideas about what might make a loud clunk noise when the weight comes off of the front suspension?

 

Could be the ball joints....

 

I looked at them and the rubber boot is intact, but I don't know how to check ball joints. Anyone know the procedure to check if a ball joint is messed up?