So we can source a nice and cheap Aston diff, right?

:-)

I'm really surprised though that the rather clever folks from the STR camp haven't figured out a dirt-cheap solution we can copy.

 

No the AM diff is different again...for some reason....

I was involved in the attempts with the S-Type guys to put a regular 8.8" LSD center in the Jag housing, it's just not possible, hence going for the Quaife...

 

it does seem strange that they are the only game in town for differentials

 

The short reason is that there isn't a huge demand in the aftermarket for LSD's to suit these 8" Gen2 differentials, well certainly not huge compared to other brands of vehicle.

You've got;

2nd Gen Lincoln LS
X202 S-Type
X350 XJ
X150 XK up to the time of the E-Diff
X250 XF up to the time of the E-Diff

And that's it, maybe worldwide you'd have 200-300 vehicles where the owner is actually interested in having an LSD, it's not a huge quantity in comparison to other brands...

As to why only the Quaife fits, if you check the dimensional drawings on the Quaife website comparing the QDF3W to the 8.8" Mustang centre, the reasons are pretty clear, an 8.8" is too big to fit in the 8" housing...

 

What about the older ford 8" LSD units? Im assuming not.

I know I read up on the lincoln LS owners converting thier Gen II to Gen I units and axles so they can have affordable LSD option. Im not nearly familiar with a any of this gen I or Gen II stuff. Information is scarse. Is that an option on these cars? (Ill assume no again and I hat eassuming things).

Now was the Quafi unit specifically made for our 8" application? I honestly have gotten lost reading up on this here in the forum. All I did get out of it was that there is only one option!

 

The old Ford 8" is completely different.

Yes one way to do it (with the S-Type) is to put in the old Gen 1 diff, along with driveshafts and propshaft, but that's a lot of messing around, by the time you've sourced all the bits it could well end up a similar cost to just putting in the quaife.

And i'm not sure if this would work with the XJ, since the propshaft would be a different length?

Another option, as Tijoe here on the forum is doing, is take a Lincoln MK8 diff & shafts and swap that, but it's also a lot of work & not sure if that'll suit the XJ either.

Yes the Quaife was specifically made to suit the 8" Gen2 diff, primarily it was developed for the X150 XK, but it's the same diff...

 

I just had my Quaife diff installed in my 2004 XJR-it's awesome. Dramatic difference even in the dry, making me question why I waited so long to do this work. This winter should be even better here in Calgary!

I'm working on a post with all the install details, including seal part #s, how to get the diff out, bearing #s, things we screwed up, etc. Meanwhile, it's like having a whole new car!

 

Definitely on my list. Look forward to seeing the job as it progressed

 

Yes its a PITA not having a LSD for these cars but so is not being able to change the ratios,s

I am liking my old XJR6 more and more (LOL)

On the side of the LSD here in Australia ford have there own version of a IRS rear suspension which comes with a LSD centre just waiting till my diff guy gets one in so we can see if its possible to fit
Not holding my breath though after reading all the post here

 

The Quaife unit does fit and work very well-if you have a 'diff guy', they wouldn't have any issue installing one. Changing ratios requires programming, but it isn't impossible, just more complicated-I know folks have looked into it on here.

 

Do you know anyone that has been able to do it and if so let us know as nobody has been located that can alter the TCM

Cheers
34by151

 

I have a guy looking into the reprogramming of the diff ratios and remapping the gearbox at the moment
He works on F1 and rally cars so is busy at the moment but we can only try
If its possible I will let everyone know

 

Some of you might be aware that the diff in my has XJR has given up & will be replaced in the next week or so.

Nothing to do with the Quaife, the pinion gear is the cause, likely because of who did the install.

Now, I have a 3.58:1 gear set ready to go in, but I'm not going to do it without the TCM programming.

If someone can do it, I need it confirmed within the next few weeks ie by mid July.

Now is the perfect chance....

 

Id liek to keep the same gear ratios and get rid of the torque management:O)

 

Well, right now i see only one option for reprogramming.
Using an engineering mode in a SDD you may try to upload TCM s/w from 3.0NA car, whic uses different gear ratio. But i'm not quite sure that it'll work and i don't have a 3.0 diff to try on my XJR

 

Tried that, didn't work. See my long thread in the General Tech Help "change diff ratio with IDS/SDD?"

 

Oops, i've missed that.

 

Does the Quaife affect the traction control system once installed (apart from it not kicking in so often)? Does the traction control need to be switched off in order to get the best benefit from the Quaife unit? Thanks

 

Here is the link to the LSD thread for the S-type/LS for those having interest in adding LSD to their car.

https://www.jaguarforums.com/forum/s...install-86430/

I will post an update on this original thread.

 

Cambo351
I just spoke to my tuning guy he said they are into remapping the torque limiters on gearboxes now but couldn't get a yes for the reprogramming of the diff ratios for the X350,s yet

I take that as no

I haven't given up as I own a 3.08 I want to put in my X350 XJ8

I will have a talk to Lachlan at chiptorque he,s pretty knowledgeable and last time I spoke to him he was playing with aussie falcons with ZF6 speeds
Might have to let him plug my car into his machine see if he can communicate with it