The injectors in the 6.0 tend to get gunk - often called a varnish - built up around the heads of the injectors. This build up causes the injectors to stick and your truck to idle horribly until things warm up and the varnish softens.
To save the injectors from early death, consider asking us to ship you out a product called Hot Shot Secret. It is designed to displace two quarts of motor oil at oil change time and gets run the entire 5,000 change interval. This product acts like a solvent to remove the varnish build up and get the injector to function properly again. Best of all, you don't need to run this product continuously. After the initial clean up, most run a 'maintenance' interval with it about once every 15,000 miles using just half a bottle going forward.