What differential is this

What diff is this: it is on my 53…but seems not original: on the left side facing rear upper flange is cast raised US PAT above 2018188, on the upper flange facing rear is US PAT 1968618. on top right rear face flange this no…18418 cast. It is a 10 bolt rear cover with the rear cover extended part for internal gear clearance about 3 in wide, the square fill plug faces rearward on the right side of the bolt on cover., it has a very clear cast raised “69” on a smooth flat on the top of left side (visible only from above), has small cast raised circle with letter “A: within followed by cast raised “44” on lower right rear face. On the bottom of the differential nose is lightly stamped:: B53 135. . The cover bolt heads each have very small raised 1035. The Differential has 46/13 tag in place(, = 3.54) I have verified that it is 3.54 by counting wheel/drive shaft turns. No where is a 4HA, or “Leys mark.
diff with US Pat numbers

Do you have the rear cover off? If so, the part number on edge of the ring gear will tell you what variety you are looking at.

Do the bearing caps look like the one on left, or the 4 on the right?

What, if anything, is cast on the rear facing reinforcing rib on the bottom right side? Is there an A? Is there a number (30, 35, 41, 44, etc)?

If you can find a BOM number, the Dana Aftermarket Media Library can be used to identify all aspects of a particular axle using the Bill Of Materials number.

good research info Mike, thanks , I will save it: but…I cleaned the axle tubes and found no numbers. No BOM…I will clean more and look more. The rear cover is on, I have never had it off…but I suppose that will eventually tell me what I need to know. From all that exterior casting numbers, US Patent, the 69, the circle A 44…the 18418…maybe the jeep rock crawler guys will know.
Nick

The A 44 would identify it as a Dana 44. There will be a production date stamped on the ring gear. There’s really is no difference between a Salisbury 4HA and Dana model 44 of that era. The Korean War ran through mid 1953. Could have been the result of a temporary shortage of the locally produced Salisbury units. The top ring gear in the photo above came from a 1955 Ford F1 pickup, the middle from a 66 E-Type and the bottom from a XK120.

i have wondered if any other Salisbury era 53…has the US patent and numbers, no Leys mark. The small circled A with a 44 is quite clear…but then I’d expect to find the BOM?? tho that is Dana on the axle tube…maybe just the Diff was the Dana part…on production 120 axletubes.


I looked in my 4HA 3.54 from a '53 FHC and the crown gear is stamped 4HA-016-9 (probably the part no. of the crown) 46-13 (ratio) STC (?Salisbury T? Company?) B53 B3 so probably means it was made in Feb '53.
IMG_20210512_174704606

We’ve talked about your axle before, and it seems most likely to be a Dana 44. I think you said your rear cover bolt heads are not Newall as mine are. If you really get curious you could remove your rear cover and look for numbers and bolt identifiers inside.
The bolt heads might tell you what country it was made in.
Bear in mind James Salisbury was the original American inventor of the axle, and sold out to Dana in 1919, but the British offshoot kept the name Salisbury.
So if you believe that the axle is original to the car, I’ll offer the guess that for some unknown reason Dana sent some center pumpkin castings or some unfinished axle tubes to England to be finished there.
Or it could be a repair job done here using an identical Dana made axle and swapping over the Jaguar specific parts such as hubs and brakes.

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Indeed STC = Salisbury Transmission Co. Ltd. of Birch Road, Witton, Brum, UK: Salisbury Transmission - Graces Guide
Chris T.

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thanks, good photo…our prior discusson fell silent about where we are now…I have yet to see anywhere a photo or description of a similar…marked axle as the one on my car…with the US Pat #s, the 69, the 18418, the circled A with 44…a 3.54, on an XK or any other car…so until I get the cover off to see the crown etc…I am interested in finding one marked same exterior…and what is it on or from…
Nick

Interesting that the E-Type one has 4HA marking, when it was a 4HU axle!

Probably the 4HU uses some of the same internal parts as the 4HA.

You’re in luck; my brother just left his 1964 Jeep CJ5 here for 3 weeks. It has a 44 rear axle.



The bolt heads are marked 20.



No gear teeth marker tag.

wow…! well skit skat how bout that…there it is…nearly the same, minor differences…but the same US PAT numbers, same 18418. So that is pretty much what is on my 53 XK120 SE…ots, wire wheels…3.54…hmmn how’d it get there on my XK, when and how did it fit…axles? etc…Now I have something to go on for parts etc…Thanks…Nick

I’m sure you are pretty safe with Dana 44 parts, but you should know that you will find those same patent numbers on virtually every Dana rear axle of any model.

Thanks Mike, I will be sure to check numbered, marked parts carefully when it is open. My diff does have a letter “A” in a circle followed by a small “44”, this photo of it. In my internet searches so far…I did not find those same US PAT numbers or the 18418. But now I have something to go on with the Jeep folks and will do some more specific searches. My diff is fine…no noises or anything, but I want to change the ratio from 3.54 to a taller one. I am hesitant tho, to have to pull the entire assembly and run into who knows what else. I wonder if it can be done in place with the fuel tank removed, car a few feet up on a hoist?
Nick

Makes me think the crownwheel & pinion will probably fit either 4HU or late 4HA.

I would think it a lot easier with the axle out on a pair of saw horses.

And just because we’re having so much fun investigating axles, here’s the front axle of the Jeep.






Near as I can tell it’s not a 44, it’s a 27, perhaps because it is a front, non-symmetrical with steering knuckles.

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Here you go. This is a Dana 41 from a 1950 Studebaker. You might more readily recognize it as a Salisbury 2HA.

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No doubt that a diff out is an easy work place. The issue is all that must be done to get it there. Does look like that with fuel tank out and up on air for comfort it would be very accessible. Wonder how they did it back then for race track changes. Jaguar decided to swap ratio for the jabbeke or 7 days run.

You swap the entire rear axle if you are in any kind of hurry. Setting the backlash on a Salisbury or Dana, which will be an iterative process, while working from underneath, will be miserable experience.

They were using the ENV axle back then. The diff change is quite simple, really. Half shafts need to be pulled clear of the splines in the diff, and then the diff unit is simply unbolted from the front of the axle housing and pulled clear. But it is HEAVY! Not much needs to come off - propshaft, of course. I think the rear brake lines don’t even need to be disconnected, but I might be wrong there. Handbrake cables would need to undone from each backplate. Exhaust, etc can stay put.
I’ve read that they changed to the 3.27 diff for the Jabbeke run. By Monthlery they were using the Salisbury (wire wheels). As my axle is JHS 1, the very first ENV number on XK120s, I like to fantasise that it may have been the one used at Jabbeke…!