Where to top up gearbox oil on a peugeot partner van 1.9 diesel?

To top up the gearbox oil on a Peugeot Partner van 1.9 diesel, locate the gearbox filler plug, which is usually on the side of the transmission casing. Use a socket wrench to remove the plug and check the oil level; it should be just below the opening. If it’s low, use a suitable oil pump or funnel to add the recommended gearbox oil until it reaches the correct level. Finally, replace the filler plug securely.