Re: 2005 Taurus weird clunking/rattle
If memory corrects me, there was a TSB about this problem with the front clip bushings slipping, thus causing that "thump". I have been getting this for some time on my 97 sable, I just have not tried the replacement yet.
If it were from the back, you might check the stabilizer bar mounts to the struts. I found mine rusted, and needed replacements.