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Are all Salisbury 4HU 3.31 diffs from Jaguar V12's the same width

Reason I ask is that there is one for sale on ebay which the seller states came from a Jaguar V12 (hes not sure which model) with a 54" wide narrow axle?

He says there are 3 different axle widths so that got me thinking are there different Diff widths

If someone could clarify please

Basically I need a 3.31 LSD diff for my XJ12 S1

Any help always appreciated

Regards

Hi Richard,
The diffs are the same width and are interchangeable but they will all, of course, require shimming to achieve the correct rear suspension geometry. Mike.

Ps I'm still looking for those bits.

Richard,
This might be worth a thought.
Early diffs had two taper roller bearings supporting the output shafts. ( E type and S type) etc
The XJ came along in '68 and had a ball race to support the output shafts.
Series 3 XJ's reverted to two taper roller bearings.

I've just been through several parts catalogues and the above is about right. I guess the early XJS the same applies. Have just looked at a 3.6 XJS Parts book and that has two bearings on the output shaft.

Back in about 1976 my '73 XJ12 suffered output bearing failure - standard axle of 3.31. The vehicle used to take off like a rocket but revved it's head off. So I replaced it with 3.07. It took the edge off acceleration but made it more useable on the motorway.

I do believe that when the XJS HE was introduced the axle ratio was also changed and I still reckon the axle ratio change made the greater contribution to improved fuel consumption.

Oldtimer

PS I still have my '73 XJ12

What condition and colour is your XJ12 S1?

Hi Richard,
It's a very early Series 2, Chassis No 1088 so number 88 off the line.
Colour - Turquoise ( sort of light green)
Condition :- All original panels, no re-spray, heavily Wax Oiled - virtually no corrosion.
Concours - no but pretty dam good

Where abouts are you oldtimer

Richard,
About two hours south of Birmingham - what about you

Try to PM me

Oldtimer