A few seconds aftercoming to a stop I hear and feel a clunking noise coming from the rear of the van, almost sounds as if rear end just caught up to the rest of the van or someone lightly tapped rear end??? anyone know what this might be??

 

Other than hearing noises, have you crawled under the van to check things out? Is there a leaking seal?

Does the rear differential have the correct level amount fuild? Remember, it uses 75W90 in there.
Putting in a heavier fluid in there will kill your mpg and mess up the limited slip function.

 

no leaks, level correct

 

Worn driveshaft univeral joints will do this.