I am in touch with OS Giken Japan, and exploring it they can make super lock LSD for F-Type. I am not aware that a better LSD for a roadcar exists, so we are aiming high
They need a donor unit to make meassurements, or we can provide the dimensions of the core unit inside the casing.

Since OE diffs are failing, do anybody have a spare old unit somewhere? Or if anybody is planning to change the diff, can you hold the core for measurements?

My plans is for V6S AT, but I guess the MT/AT difference is just the final gear so if any MT folks want to chime in maybe it can be done too. Now the problem is to find out, if the OS Giken core can fit the OE housing.

 

I believe that a similar effort was proposed already, but with Quaiffe. There are several units that were used, depending on whether the base open diff, mechanical LSD, or e-diff. I don't know how interchangeable they are.

EDIT: A quick search turned up this discussion:

https://www.jaguarforums.com/forum/f...r-mods-153888/

 

I know, but I don't want Quaife and also the effort went nowhere.

 

I was pointing that out for informational purposes. It seems that you were speaking as if there was just one that covered all model options.

 

Are you wanting a clutch type diff to be built for it? It may not be the most daily driver friendly, if anything a helical would probably be a bit better for that.

Another option if you were looking for a clutch type would be Kaaz, I deal with them pretty regularly and their new “super q” line of clutch type diffs are pretty nice for road cars but still a bit noisy in low speed/high steering input situations.

also, I haven’t researched much as I just got my F type, but what exactly is breaking in the OE diffs, ring and pinion, or parts in the differential itself?

 

It went nowhere because the offered donor pumpkin never materialized. I still think the Quaife is a better road/track choice than a clutched LSD or even a locker that might be best for a track dedicated car.

 

Guys, I really don't know why you don't research OS Giken at least a bit. It is the rolls-royce of LSDs, It is smooth, silent, progressive, mainanace free except fluid and does not open like any Torsen/Quaife diff. Also, it is tunable where you can ajdust preload, and you can have 1, 1.5 or 2 way diffs. You really can't want more from a diff than this. Kaaz is not in the same game. OS giken have several patents and thats why nobody comes even close to them.
Also, even that I have tried a lot, I could not find what exact diff construction we have in our cars. I guess my only bet is to buy some used diff and measure and examine it myself.

 

We're back to the issue of there being at least three different rear differential assemblies fitted to the F-Type. Since you have no signature identifying which model variant you've got there's not even that to go on. I don't know of any information on the actual differential unit within them, but between different types and different ratios, I would not be surprised if a single unit to fit all is a practical impossibility.

 

My concern as well.

 

I clearly said in my first post in this thread I am looking for V6S AT.
Changing ratios are easy and if VS6 AT will work I am confident you there is a possibility for other models as well.

 

https://www.ebay.com/itm/Rear-Axle-D...kAAOSwcZpc~~EX

 

Ah no, changing ratios is not easy in these cars... there is only a small tolerance allowable, anything beyond that will require special programming.

Between the 3.15 & 3.31 is probably "close enough" to avoid programming.

That diff is from a V6, non-S, it has the 3.15 gears, the V6S has 3.31

 

I thought about changing the final gear for the diff manufacturer. Like they can do more versions for more cars.

 

My apologies. That was over a week ago. These days, I can't remember what I had for dinner last night.

While the V6S AT isn't a bad choice for development, if not applicable to the MT or to the V8 variants, you lose potential market. It's possible it'd work, but I just don't know. I've rebuilt many dozens of transaxles, but for a single marque. I think there might have been two different ring gear carriers over a 20 year span, but I don't have high expectations that there will be the hoped-for interchangeability.

 

I've got a failed diff that needs replacing, located in Italy. Considering the inside of mine is probably trashed, would it be any good to you?

 

If you got V8 you have e-diff. We need the dimensions, so even trashed could work. I suggest you keep the unit and if I find V6S then we can send both to OS giken.

 

What exactly is failing, the mechanical differential unit itself, or the ring and pinion? If the ring and pinions are failing an upgraded diff will really do nothing to remedy the issue.

 

good question, this is exactly my thoughts also.

 

In case anyone is interested in the diffs:
340 AT: T2R17980 3.15 ratio Open
340 MT: T2R18657 3.31 ratio Open
380/400 AT: T2R4000 3.15 ratio LSD
380 MT: T2P1783 3.31 ratio LSD
5.0L: T2R22213 2.56 ratio ELSD

 

Are you sure? Thought the V6S auto was a different ratio than the base.