I noticed that my Transmission was wining really bad, so I checked the gear oil when I got home... none.    Started to add fluid and it all just started pouring out onto the ground.  Got underneath and my transmission drain plug is missing.    Anyone have any idea what size / pitch the plug is or where I can get a replacement for a Gen1 Brat with the 4 speed manual. 

Well, no replies. 

 

Here is what I have done so far.   I got underneath with pair of calipers to measure the hole.  Looks like its 24mm.   If its a common thread pitch, then it might be a 24 by 1.5mm plug.  I looked up what other more modern cars have that type of plug and had to special order one from Napa.   Ill get it tonight and see if its fits then report back with the results. 

Sorry I can't help you, but thanks for updating the post.

Good luck.

Wasn't NAPA able to look it up? They were able to look up '82 Renault lug nuts, I assumed they'd have cross reference to drain plugs.

Napa only had the oil plug in their lexicon of parts.  However after spending to much and some trial and error I was able to find the right size.   It is a 26mm by 1.5 pitch plug.  

 

They are not very common, but they were common in older Mercedes.   The one I used was a 85 380SL  Fits snug, and isn't leaking. 

 

Here is a link for years and models 

http://www.partsgeek.com/ss/?make=Mercedes&ssq=W0133-1640723&brand=Febi

Thanks for posting the cross reference! Don't need one now but its greasy to make this stuff easy to find.