Clunking noise when shifting, but not always. It

Clunking noise when shifting, but not always. It happens on hard acceleration AND low acceleration. I have had the rear end completely gone through. Replaced rear differential. Mechanic said it was sloppy. Some of the clunking noise is gone now, but I still have some. Seems to be coming from front end.

Also when coming to a stop the truck seems to rock forward after a complete stop (nose dip)more than usual. I dont think it's the supension. It almost feels as something is loose. After I take my foot off the brake there is a slight noise.

Thanks for the help!
-gotpmac