GM and Ford have both been talking about doing this for several years now. I believe that these trucks would have already been out had oil makers been able to stabilize diesel prices earlier.
I'm out on any first year production. I worked as a service advisor for a Chevy dealer the first year the Duramax came out...It was nothing nice!
There has been rumor that Toyota will be making a half ton diesel in the coming years as well. If they do, American manufacturers are really gonna be in a bind!