Newb question about filling differentials

[Lriwater]

Okay folks. I searched and found nothing. How do you fill the diffs on a Series III? I have a drain plug but no fill plug. Sounds like a stupid question to me , but I'm baffled.
Thanks in advance.

 

[Leslie]

The front diff probably has one on the front of the front pan; but on either diff, in the webbing of the 3rd member, on the back side, is where you'll find the square sticking up for the fill-plug. As you're facing the backside of the diff, beside the driveshaft yoke, it'll be just to the left.

 

[66rover99]

My front one on a series IIa only has a filler on the front of the pan, and not on the webbing... so, it's conceivable that if you're talking about a rear diff with no pan access, and someone over the years replaced it with an older front diff with no access on the webbing, that you actually could end up with no filler plug. Hmmm, could take out an axle and insert a long tube and pump some in that way...

cheers, Dave

 

[Ron]

You can drain it fully and fill the estimated amount needed by removing the breather and using a tipped bottle.