Front end noise

I have a 1998 Chevy S10 Blazer, 4wd, V6, with 84,000 miles.
My problem is that when I turn the wheels hard either left or right and go forward or reverse (like when parking) I hear a clunk sound as if something is popping out of joint.
I had it in the shop recently and they replaced the idler arm as well as the lower front ball joints. In addition, they found and replaced broken motor mounts.
Control arm bushings also were checked and look good.
They have checked over the entire front end more than once and can't seem to explian this noise.
So, on the advice of a Chevy mechanic friend, I am taking it back to make sure all the grease fitting are properly lubed and hopeing for the best.
How many grease fittings are there in the front end. So I can make sure they find all of them and any thoughts on the "clunk" sound?