Jaguar Diff Ratios

[rover]

Guys anyone have a list of what diff ratio is in what model Jag.It would be useful to you have the details for both the XJ6 and XJ 40

[mclark]

This was taken from the Dax De Dion donor list doc. I also believe there was a 4.07 (or around that).

Differential unit assembly
RATIO XJ40 DONOR MODEL TOJEIRO ENGINE RECOMMENDATION
3.77:1 2.9l Manual Rover V8 (geared for maximum acceleration)
3.54/3.58 3.6l Auto Rover V8 (geared for touring) + Ford/Chevy Small Block + Ford/Chevy Big Block (geared for maximum acceleration)
2.88:1 V12 (Very Rare) Ford/Chevy Big Block (geared for touring)

Note 1 – Check stamping on identification tag (held by diff rear cover plate fixing bolt) to confirm ratio
Note 2 – Power lock differentials were a customer option for UK XJ40s and are therefore fairly rare

Regards

Michael

[rover]

Thanks Michael It looks like a trip to the library to hopefully fill in the gaps. I thought that there is a 3.31 :1 also. Have you sourced all your bits yet ?

[mclark]

I have, yes. It took me a while but then only to find out the guy had a few XJ40 diffs and he's only 5 minutes from my house :} :} :}

Now have a XJS 3.54 Powerlock up for grabs.

Michael

[nbracken]

Hi Rover, on the pre XJ40 series I believe there were 4 ratios

2.88
3.07 - 4.2 litre auto's
3.31 - also 4.2 litre autos
3.54 - all 3.4 litre cars and 4.2 litre manuals
Not sure which the 2.88 came from - maybe XJSs

Power lock LSDs were avialble as an option

Rgds