Topic: 67 9" Housing Fill Plug Compression Washer

[Bossbill]

My 67 9" has both the housing and differential fill plug.
The housing sports a very large machine screw-in plug.
It also has a large, flat aluminum compression washer between the plug and the housing.
Both the plug and the housing have a taper on the mating surfaces, so the washer also becomes tapered.
I looked in various places and could not find a replacement washer, so I made my own. The old one was very corroded and had sealant on both sides. It sure looked original.
But that does beg the question . . . Is the washer stock?
[the washers are the same size if you take into account the corrosion and loss of material on one side].

[edit title and content to be 'washer' not 'ring']

[RoyceP]

The Master Parts Catalog does not show any gasket being used on the differential housing fill plug.

[Bossbill]

I did check the illustrations in the 60-68 MPC and had no luck there either.

But I think I figured out why. 1st pic is of the special notations added to part numbers.
2nd pic is a snip of section 4010, 'Housing Assembly -- Rear Axle'.

Reading  through the section there is a callout for part 379266 noted as 'Plug (filler)'.
This matches the illustration you showed of the MPC .
However, the plug actually installed in my car is 'Plug (filler) 7/8"-18 hex. beveled'.
The housing is beveled to match only to a beveled plug. I'm not sure why the MPC illustration doesn't list the other plug options.

Further down is this misinterpreted/misspelled entry:
'*352733-S100    1   Washer(plug sealing) - 7/ 18" flat'.

I think the entry should read '7/8"-18 flat' not '7/ 18" flat'.
I believe this is the washer in question. The -S100 denotes 'special', which in this case could be for 'aluminum', perhaps.
And finally the * notation indicates 'Not serviced', which may be why it's not in the illustration.

[jwc66k]

Washer, 352733-S100, is documented in the "Ford Standard and Utility Parts Catalog, January 1969 (AM0205, pg89) as - Washer, Flat, 7/8 ID, 1 23/64 OD, 1/32 T, Alum-rubber.
Jim

[Bossbill]

So that's what's on the washer! Rubber, not sealant as I thought.
Good find. Thanks.