How do you change the gear oil in a 1995 240sx'S?

To change the gear oil in a 1995 Nissan 240SX, first, ensure the vehicle is on level ground and securely lifted. Remove the drain plug from the differential and allow the old oil to completely drain out. Once drained, replace the drain plug and use a pump to fill the differential with new gear oil through the fill plug until it reaches the appropriate level. Finally, replace the fill plug securely and check for any leaks.