Does the Boeing 737 NG have "5" radar altitude callout?
The Rockwell Collins EGPWS, that is probably the most widely used system (you can tell right away by the voice that sounds exactly like the character "Data" from Star Trek - Next Generation; I'd swear it's the same actor's voice) comes with the full range of callout altitudes/heights and airlines pick and choose which ones they want by "configuration strapping" settings (connector pin jumper configurations in the mounting tray) when the units are installed in the avionics bay.