How do you remove the fill plug on the differential on a 1983 C10 (2WD). This is the 10-bolt rear end. As far as I can tell, the fill plug is on the passenger side of the diff and requires some sort of special tool. Either that or the previous owner stripped it out. At first I thought it was an Allen or Torx type nut. But it's mostly squared off - it seems like something between a 3/8 and a 1/2 ratchet would fit. Any ideas ? Do I need to buy a 'Pipe Plug Socket' ? Those aren't too easy to find from what I've seen. Only online so far through www.etoolcart.com Any help would be appreciated. Thanks.
This has been answered on this link.https://talk.classicparts.com/showthread.php?t=7996 If it is rounded a bit press down as hard as you can turn as slow as you can with steady pressure, lube with some kinda antirust penatration oil let it soak in. good luck.
Another way is to forget about the plug. Remove the cover and install a fill plug into the cover. Drill a hole about the fill level of the diff and weld a nut on the outside of the cover and use a nut as your plug. easy fix and low cost