How do you change out the serpentine belt to a ford excursion diesel?

To change the serpentine belt on a Ford Excursion diesel, first, ensure the engine is off and cool. Locate the belt tensioner and use a wrench or socket to relieve tension on the belt. Remove the old belt by noting its routing or referring to a diagram, then install the new belt following the same path. Finally, release the tensioner to secure the new belt in place.