I've committed the classic newbie mistake of draining a fluid before making sure the fill plug can be removed. Actually, I'm not even sure if I found the fill plug. There's some kind of square drive which may be the plug on the passenger side, a little towards the front of the vehicle, a little over halfway up. My 3/8 extension doesn't quite fit though, the extension seems a little too big. Can't see any other plugs, and my Haynes is no help.
Can anyone please confirm the location of and tool needed for the rear differential fill plug on a '87 S-10 Blazer 4WD?
Thanks!!