Any idea what this is? This is on my '79 F100 2WD. It looks like a Dana 44, but doesn't have a "44" on the pumpkin. I remember trying to look up the axle code at one point and it wasn't listed. I've tried to make out the tag as best I could, and here's what it appears to say:

2 72ED-D9TA-A3A
75 1739-2 MEZ (not as sure with this last line)

Axle shaft tube:
751739
21 5 79 A (guessing this is the date)

Door tag: 11J

That axle shaft number appears to be a Spicer number, but I can't find it in any Spicer literature. In all likelihood this is probably a Dana 44, but maybe someone with the books can verify. It needs a pinion seal. Thanks for the help everyone!

 

I thought the Dana 44 was a heavy-half-ton(F-150) ?
Sorry,I am just a little confused...

 

It IS Dana 44. Whenever I search for the Dana 44 rear axle, I rarely get anything. Ford's redhead stepchild axle or something. I've owned a few parts trucks that had a Dana 44 rear axle, so they do exist.

If your axle code is 11J, then it's a Ford 3750 lb open axle with a 2.72 ratio. Parts catalog sez there isn't a rear axle code of 11 in 1979. Latest was 1978 only. While it says Ford, it's actually made by Dana.

 

Wonderful. I was hoping you would see this thread. Thanks again!

 

While the Dana 44 axle is common, they do come in a variety of sizes and configurations as they were used on other makes.

People always think half-tonners always had a Ford 9" in the rear. Nope.

If the ratio is a strange number like 2.72, 3.07, or 3.31 then it's an uncommon Dana 44/61 axle.

If you have trouble finding one, PM Bill / NumberDummy so he will know to check this thread out, I'm sure he knows the so called mystery of the Dana 44 rear axle.

 

C6TZ4676A .. Pinion Seal / Dana/Spicer part number: 35723 / National Seal part number: 5778 R54

11J:

11 = 1978/79 / Dana 44-3 / 2.72-1 / Non Limited Slip / 3750 lb. Rear Axle Capacity

J = Power Steering

Chad's version of the '73/79 parts catalog is on a CD and was scanned from an early edition.

While I have the printed version of that one, I normally use the last version dated 10/88 on Ford microfiche slides.

The early edition has errors and omissions.

There is no D9TA-A3A. The 3 is either a letter or the numeral 1 or 2.

The Dana ID number is either 7 or 8 digits long, begins with a 6.

Some 1977/79 F100/150's use Dana 44's...with "Hi-Speed rear end" ratio's like 2.72-1; 2.79-1; 3.07-1.

Ford did this to improve fuel economy...which after the first Arab oil embargo (1973/74) ended, became a national issue for the very first time.

Prior to the first oil embargo, a gallon of regular gas nationwide was between 20-25 cents.

When the embargo ended, the price had risen to ONE DOLLAR a gallon, higher in some states like CA.

Gas prices went up again...after the second oil embargo of 1979.

 

Thanks for the insight, Bill.

I still remember the odd/even days.

 

Wonderful information; thanks for the follow-up Bill.

 

FYI, but unrelated to 1973/79's.

1959/68. If the F100 has Limited Slip, the rear axle is a Dana 44! The 9" with Limited Slip was only available in passenger cars.

1961/68: While the Dana 44 came with Limited Slip, Ford also offered a Dana 60 for F100's. This 60 was available with/without Limited Slip.

With this Dana 60, the wheel bolt pattern is the same as other F100's: 5 lug, 5.50" bolt circle.

 

Resurrecting an old thread: Re. Bill's assertion that there was no A3A - my tag is identical to the original poster's except I read the last group as MEX, thinking this was a Dana manufactured in Mexico. I see no other way to read the first line's last group than as A3A... pic attached.

My primary question: given this is an F100 with a 2.72 diff, any educated guesses on whether this could be converted to somewhere near a 3.25-3.50ish ratio easily? I am told that with a good 300/C6/2.72 I am looking at a tow capacity of about 2000 pounds - by changing to the 3.25-3.50 ratio, roughly how much would I increase the tow capacity?
(No need suggesting reading the door, the original door was replaced with an F150 door before the last owner got it.)