You change the engine oil as normal.
The transmission you have to drain the torque convertor or flush the convertor. Look here for a good write-up: 4R100/E4OD Trans Flush Procedure - Powerstroke Nation
FWIW, I have been running Amsoil heavy duty diesel and marine oil for the last 150,000 miles. Oil analasys has always come back lower than normal averages.
I just today took off my dual remote/bypass and switched back to Delo 400. The Amsoil will hold up to a single HPOP truck for 18-20K miles without any problems. Over half those miles are towing. After I switched to my twin HPOP's my oil will only last 10-11K. I can get 5K out of dino oil so I did not find it a financial advantage to run Amsoil in my truck any longer.