How do I check the gearbox oil on VW transporter year 2000 1.9 diesel?

To check the gearbox oil on a 2000 VW Transporter 1.9 diesel, first ensure the vehicle is on a level surface. Locate the gearbox drain plug, which is usually found on the side of the gearbox. Remove the plug using the appropriate tool; if oil seeps out, the level is adequate. If not, you may need to add the specified gearbox oil until it reaches the correct level, then replace the plug securely.