The conversion has been done in an S-Type R, the parts are interchangeable (same diff & driveshafts used on both X350 XJR and S-Type R according to the parts catalogue).

 

Looks like I am out of luck on a Quaife QDF3W. I was hoping I could get one for $1300 delivered including an estimated $120 tariff.

Motorsport UK do not have any they are no longer able to get them.Reason being that Quaife sold all they had to a company called XKR Transmissions in the UK.

No web site and their phone messaging service is full so cannot talk to anybody or leave a message. Does not sound good at all.

 

Did some basic research and it looks like this could be a no go for me since the wheel hubs look to be different between the S-type and X350 and I would guess everything that is connected to the wheel hub as well?

 

The rear hubs are the same on the S-Type and X350, same part numbers.

The rear hub carriers are the same on the Brembo-equipped S-Type and X350, same part numbers.

The half-shafts are the same on the 4.2 s/c S-Type and X350, same part numbers.

 

Quote:
Originally Posted by Cambo View Post
The axle shafts as you call them, are not the same between the 4.0L S-Type and the later S-Type & X350.

However the propshaft is compatible.

If you want to make the 4.0L diff conversion, you need the diff and the axle shafts / half shafts.

Then swap the gears out of your diff into the 4.0L one, along with the LSD." End Quote

I am trying to wrap my head around this for a Ford 8.8" 28 spline LSD conversion in my 2005 XJR.

I need a pre 2002 4.0 S-Type diff and the half shafts from same vehicle.

My existing prop shaft is ok.

What about the rear hub carriers that I need to fit the 4.0 S-Type half shafts?

I presume I need these from a pre 2002 S-Type as well?

Will the rest of my 2005 XJR Brembo brakes etc fit around the 4.0 S-Type hub carriers?

 

4.2L S-Type R and XJR have all the same rear end components; diff, halfshafts, hub carriers, hubs.

A 4.0L S-Type diff and halfshafts bolts in to a 4.2L S-Type R (has been done in the UK)

Therefore 4.0L S-Type diff and halfshafts bolts in to a 4.2L XJR.

You need to change the 3.31 gears in the 4.0L diff to the 2.87 gears from the 4.2L diff. Or reprogram the VID block to accept the 3.31 gears.

The 4.2L propshaft bolts up to the 4.0L diff.

The Ford 8.8" 28-spline diff center fits inside the 4.0L diff, and the gears from the 4.0L and 4.2L are interchangeable.

I don't know how to explain this any clearer.

 

Got it. Thank you Cambo.

 

I am embarking on the 4.0L S-type Diff route. Already locating parts.

I was thinking of replacing boots on the half shafts BUT very expensive unless I can locate alternatives.

We will see what the condition is of the used ones.

This will take a month or so as I need warmer weather!

 

Cambo, do you know examples who managed to reprogram it? Or it is still a theory? Thanks

 

It would have been nice to be able to reprogram the appropriate vid block however....

I plan on using parts from a lower mileage, than my car, X350 differential in the 4.0 S-type differential along with the ford LSD. I located one at what I think was a low price after some "negotiation".

All parts except for bearings are on order. The Ford LSD is not expected until January or even February! I did not notice the extended delivery time on it when I ordered it but it was the best price I could find for a new unit.

I am hoping to be able to have the completed rebuild/ replacement diff ready to swap in without having my car out of action for very long.

Have been studying Youtube videos on diff rebuilding.

Having said that I do plan on checking all bushings etc while I am in there and if I need new parts I will replace.

 

I don't have any examples to share yet, but it's been tested on a couple of X350 & X202, it is possible to change the diff ratio.

 

Please tell more! Who where when? we have to prove it or forget about this dream. Really, let's stop dreaming and upset owners by unmet expectations.

 

Would you prefer NOT to have updates, so you know what's been done?

Anyway... I like hearing about the progress so stick with it please Cambo

 

+1 on that.

 

One pic is of a 2005 XJ half shaft and the other a 2001 S-Type 4.0 half shaft.

Quite a difference. It does not look to me that the S-type will simply fit in my XJR?

The project is to make an LSD using the 2001 S-Type 4.0 diff to fit my 2005 XJR.

The S-type has raised timing notches and the XJ has indented slots.

My choices appear to be to see if the XJR hub end will transplant on the S-Type half shaft and failing that
to chop the XJR hub end and have it welded onto the S-Type half shaft.

Any comments?

 

Must be that they swapped the outer CV joint assembly from one shaft to the other then...

 

I will do some careful measuring and see if I can do that.

 

Apparently there was a bit of a mixup with the outer CV, xdave explains a little bit here https://www.jaguarforums.com/forum/x...04-xjr-167725/ not sure if that is something to keep in mind or not...

 

I actually read that a while ago and had forgotten.

Could be an issue for me.

Will see in a week or so what I come up with on the half shafts.

 

2006 Super checking in,


This is what mine looks like under the car. Not sure when the style was changed, I didn't have a chance to look through JEPC or anything yet, just wanted to get this out to everyone.

It's easy enough to snap a pic with a phone even if the car is on the ground and on its wheels, if anyone is wondering which style ABS ring they have.

Also, I haven't looked into it, but it may be an option to replace the ABS pickups to work with the 'toothed' kind of ring.


Edit: Lovely pic also shows me I need new Anti Roll Bar Links and Stabilizing Links. Crap, more to do 'while I'm in there'