My '83 300TD has a 13mm drain plug. For some reason my '80 SD has a 12mm. Just get a standard set of metric wrenches, both sockets and open end ones.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
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