The Mercedes-Benz GL320 front inner turn signal requires a 3457NA bulb size, while front turn signals use either 3457NA or 12961 bulbs, and rear turn signals require PY21W or 12496 bulbs. The replacement chart covers 2007 to 2009 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.