Has anyone ever looked closely at the internals of the mid-80s Dana carrier (without drain plug). I've found exactly one off-hand comment on the internet hinting that it had other than 19-spline output stubs. I'm wondering if it might actually have 30-spline output like a normal Dana 44? I found the picture below of what I'm almost certain is the Jaguar Dana diff in question. Definitely more than 19-spline output, but I can't tell if 30-spline. Ultimate goal would be to find easy way to use standard 30-spline Dana 44 carriers in the Jag IRS. e.g. Torsen T-2R for standard Dana 44 axle with 30-spline

 

Duplicate glitch, see next post

 

The DANA 2.88:1 diff as fitted to the XJS V12 in the mid 1980s has a THIRTY spline count. I know this for a fact as I am in the middle of a rebuild of mine!
Interestingly I also intend to fit Torsen LSD-type internal, in fact this one:
https://www.drivetrainspecialists.co...rac--rear.html
These guys at DTS are brilliant, and I spoke with a very decent guy called Rich there who was very helpful and knowledgeable. The crownwheel off your old Jaguar DANA diff is a direct fit, and this Truetrac Torsen diff above is even drilled for the Jaguar bolt size. The Jaguar DANA casing is not the same as a solid-axle DANA 44, the Jaguar DANA has a short stub axle (output shaft) that runs in a huge sealed bearing that presses into a machined casting that bolts into the side of the casing. That is why you need a Jaguar DANA casing to start with. This is photo of the output shaft with the bearing - which you cannot see - in its machined casting, which has the three bolt fixing that bolts into the diff casing.



The DANA stuff will not, repeat not, fit into the Salisbury/GKN diff as fitted to most V12 pre facelifts though. You have to have a DANA from a V12 to make this work.

Greg

 

Fantastic! Thank you for the confirmation and additional info. I already have a line on one of these at a nearby scrapyard. Plan for the car (1972 XJ6) is to drop in complete front and rear suspension from 1995 XJS with outboard brakes, but the 19 spline output shafts were a big question. I’m happy to know there’s an easy path to a Torsen type diff.

Greg

 

The XJS with the DANA had inboard brakes, but that is easily overcome with a spacer if you are using an outboard braked axle from a late-model XJS, I have a feeling that the spacer will be there OEM on the outboard braked axle. The 30 spline output shafts will bolt up to the outboard braked driveshafts just the same.
I would be very grateful for any info you can give me about the actual swap when you get round to doing it.
It is worth checking that the axle cage and driveshafts are the same dimensions width-wise in a Series I as in the XJS.

 

Best I can tell from online research, the front and rear suspension is effectively interchangeable (as complete subframe assembly) on XJ series 1,2,3 and XJS from 1968 to 1996. Same overall width, same subframe mounts and everything. As you mentioned, I'll need to deal with inboard vs. outboard brakes if I go with the mid-80s dana housing. This should be trivial with spacer in place of inboard rotor. Or, maybe 30-spline output stub shafts can be easily adapted to the Salisbury housing. We'll see, not too worried about it now that I know of the 30-spline unicorn. I also expect that something different will be needed to connect steering column to the rack. Not sure what yet, but lots of information about newer racks being better but have taller tower. But, wouldn't be a project without some fabrication. That's what makes it fun.

Greg

 

Hi Greg,

Will this Torsen LSD fit directly into a 3.54 XJS diff head also?
(The 3.54 came from the 3.6L inline six, manual gearbox car)

I also have a 3.31 LSD from a series ii XJ. Would that work?

Cheers
Craig

 

I am not sure. I think they 3.6 litre diffs are Salisburys, so the spline count is different (19, I think) and the fixing method of the output shaft is different. BUT, the Truetrac Torsen does come in a 19 spline version, so providing you have a Salisbury Jaguar diff to start with, it could well be a drop-in too. There are two models of essentially the same Truetrac LSD unit made, depending upon the ratio of the diff. The link I posted is for ratios "3.73&DOWN". A numerically higher ratio is another model for diffs with a numerical ratio of above 3.73:1 (eg 3.9:1).
If you speak to the DTS guys they know all about Jaguar Salisburys and will for sure be able to say if there is a Truetrac that will be correct.

 

Thanks Greg...