My 2003 F250 4x4 has developed a clunk when I stop. If I shift into neutral as i slow down, no clunk. (I had a similar issue with a 76 chev when the transfer case drive chain wore out.) Sound familiar to anyone?

 

check the play in your driveshaft ujoints?

 

The clunk turned out be the front ball joints. They were checked twice and passed tolerance the first time. The second time they showed way out. I don't understand how come they were quiet one week and clunking the next, but replacing them solved the problem. The universals seem tight.