clunking/clicking noise

I've had this clunking/clicking noise for awhile now and i need suggestions what to inspect.  It doesn't matter if i drive 5 miles an hour or 65 it still will make noise.  It's not  constant but will clunk every 3 to 10 seconds.  The weird thing is if i hit the brakes the noise will go away.  I can't pin point the location it seems like it's coming from under the truck on the drivers side.  I've had all my u-joints replaced and checked the exhaust system.  What would stop clunking when the brakes are applied?  It's a 99 blazer six cylinder 4x4.  Also 4wd works fine i've been using it the last couple of days, and it makes the same clunk while engaged in 4 wheel.  Please post some suggestions i don't want to take the truck to a shop just yet.
 
thanks

Could be ball joints