How do you check and change manual transmission oil Mazda 6 2005 6 speed?

To check the manual transmission oil in a 2005 Mazda 6 with a 6-speed transmission, locate the fill plug on the side of the transmission. Use a socket wrench to remove the plug; the oil level should be at the bottom of the fill hole. To change the oil, first drain the old fluid by removing the drain plug at the bottom, then replace it and fill the transmission with new oil through the fill hole until it starts to seep out. Finally, reinsert the fill plug securely.