How do you Change idler pully 2003 dodge 2500 diesel 5.9?

To change the idler pulley on a 2003 Dodge 2500 Diesel 5.9, first, disconnect the negative battery cable for safety. Use a wrench or ratchet to relieve tension on the serpentine belt by turning the tensioner pulley, then remove the belt from the idler pulley. Unscrew the idler pulley from its mounting bracket using the appropriate socket, install the new pulley, and reattach the serpentine belt. Finally, reconnect the battery cable and ensure everything is secure before starting the engine.