My money's on 17mm.
I have a 92 Diamante Wagon. And the drain plug on my car is on the bottom left (driver side). You need a 22mm socket wrench to open it. Hope that helps.
It takes a 15mm wrench.
The 1997 Mitsubishi Diamante OBD 2 port is under driver side dash next to center console
not sure exact size but Mitsubishi is japenes, thersfore it is a mretic wrech u need
If it's the "oil" drain plug, the size wrench is, better yet use a socket wrench=13mm.
If the drain plug is original equipment, it takes a 17mm wrench or socket.
To change the oil in a 2003 Mitsubishi Diamante, start by warming up the engine slightly to thin the oil, then turn it off and let it cool briefly. Place a drain pan under the oil pan, remove the drain plug, and let the old oil drain completely. Replace the drain plug, remove the old oil filter using an oil filter wrench, and install a new one with a bit of new oil on the gasket. Finally, pour new oil into the engine through the oil fill cap, checking the dipstick to ensure the correct level.
To remove a drain plug, locate the plug underneath the sink or tub, use a wrench to turn it counterclockwise, and then pull it out.
15mm
To drain the transmission fluid on a 1991 Mitsubishi 3000GT, first, ensure the vehicle is on a level surface and securely lifted. Locate the transmission drain plug underneath the transmission, and use a wrench to remove it, allowing the fluid to drain into a suitable container. After the fluid has fully drained, replace the drain plug and tighten it securely before refilling the transmission with the appropriate type and amount of fluid through the fill plug. Always consult the owner's manual for specific fluid specifications and capacities.
draining a radiator of a mitsubishi space wagon
The original engine oil drain plug wrench size should be 15mm.