Mistery differential

[Klapatta]

Can anyone identify this rear end? I need to do a complete reseal job on it.
It's of late 1950s vintage. I have been all over the internet trying to gather information about it and the more that I take in the more confusing things become.
It seems to have common traits with the Chrysler 8 1/4" or Ford 9" but is neither.
The ten spline input accepts a 1 5/8" yoke

Ten bolt mount pattern that is a circle.

Ford type axle retainers
Brake backing plates are stamped fomoco and are fitted with 11" x 1 3/4" linings.

Spherical case much like a Chrysler 8 1/4"
Factory drain plug at bottom.

Any help telling me what this is would be appreciated

[mmzullo]

FoMoCo is Ford Motor Co if you didn't know that already. I bet if you go to cruise nights some street rodders will help you out.

[BigMike]

If it isn't an 8-3/4 Chrysler then it must be an 8-1/4 but definitely looks to be from Mother Mopar.

[SWilliams]

Looks a like a Timken built unit used in the early Fords. Prior to the 9 inch.

[ridgerunner97]

8.25 chrysler was never a drop out axle. Only 8.75 chrysler was dropout, I think the 7.25 chrysler may have been drop out as well in a car application. Big Dodge Trucks had different types of dropout axles in the 40s, 50s, and 60s.

[albie]

7 1/4, 8 1/4, and 9 1/4 chrysler axles are all rear load with c clip axles. The 8 3/4 is a front load but wouldn'thave any fomoco stampings. I also think the 8 3/4 chrysler is not as long in he pinion area. just my $.02

[BigMike]

It's stamped with FoMoCo?

[mmzullo]

Definitely Ford. Look here http://www.mustangandfords.com/techarti ... to_05.html might be more. try here also. http://www.drivetrain.com/parts_catalog ... gears.html

[Klapatta]

It's Ford alright but from out of what, I need to give Napa a year and model to obtain seals and a gasket.
For a time I was suspecting the Chrysler 8 3/4" because of the spherical case and ten spline input pinion. The Chrysler 8 3/4" has the carrier mounting studs at the 11:30 and 12:30 positions, however this one has the top stud at 12:00 like the FoMoCo 9 inch does. Also, the Chrysler is 8 3/4" cast and tapped for a top snubber mount, no provision for that here.
That being said, this is not a 9 inch as those carriers are not shaped in the form of a true circle as this one is and I can put a socket on the bottom two studs- you can't do that with a nine.
The heavy Ford axle is used as the medium duty axle has a D shaped relief cast into the flange face. These have the three end holes designating heavy duty.

The oddity here is the medium service brake backing plates are used, the 3/8" instead of 1/2" flange mounting holes designate that and also the 11" brake linings are only 1 3/4' wide, not 2' or 2 1/4" as found on the 1957 and up 9" rears.
Also, the brake drums are marked FoMoCo.

DSCN1961.JPG (28.77 KiB) Viewed 4944 times

I'm starting to suspect this is is a pre 1957 Timken unit as Steve chimed in with, (thanks Steve) however I have yet to actually locate an image of one on the internet to verify that.
Someone once said to me that it is a 1950s Plymouth unit like the kind found in the CoPar Panzers- no way.
I am preparing to load the thing up into the truck and take it to Napa and the Ford dealership and get ready for a lot of blank stares
Thankin everyone for the input- I'll let ya know-

[l palma]

Saw this on cl looks just like yours.

http://reading.craigslist.org/pts/3056184701.html

[Klapatta]

Very helpful and interesting Lewis, thank you much- so that's what an unmodified one looks like.
Looking for parts with some paper printouts sure beats lugging that thing around all over the place
This was all that I had to go on with until yesterday

Oh by the way it's a pre 1957 rear end, the nine inch replaced it.
Showed the pics to the manager at Napa, he typed in 1954 for a year and all the seals are on the way