To my understanding, the halfshafts for the automatic are T2R16044 while the halfshafts for the manual are T2R7755.

Not sure why they differ. Different peak torque?

 

OOOPS.. correct.. my mistake.
All manuals had 3.31 ratios.
@jlsthlm

The prop shaft (from the output of transmission to the rear axle) is a different part number probably due to the length .. as automatics can be "longer" than a manual gear box (or vice versa?)
I have done some Volvo automatic to manual transmission conversions, and I always had to get a longer prop shaft, due to the shorter manual gear box.

The half shafts (between differential and wheel) should be the same length... and I am at a loss as to why they would be different on a manual car... wow... can't think why it would demand a different part number.
I will consider myself forewarned.

 

Update:
I investigated the Ford 8.8" rear differential as a possible source for LSD's... based on a few factors:

• the SPICER label on the Jaguar part, which suggests a connection to a supplier to Ford
• the 31 spline axle shaft with 1.32" OD which is a Ford staple
• the rough 8.8 " OD of the ring gear from the Jaguar differential.

Well.. no dice.

• although the axle shaft and spline seem to be the same between the Ford 8.8 LSD and the Jaguar carrier...
• no other dimension is the same..
• not even the ring gear bolt pattern (could be a difference between metric and standard?)

The Jaguar diff is "skinnier" and the bearings are larger.. and the flange is thicker.
So Jaguar commissioned a custom design w.r.t. the Ford 8.8... probably to have a proprietary design.

Next Steps:
see if the spider gears and LSD components can be swapped into the Jag carrier (probably not).
search out possible SPICER sources for LSDs in the custom Jaguar format? (probably an OEM only part... with limited supply agreement)


Ford 8.8" LSD vs. Jaguar F-Type open diff

 

The Spicer Performance web site does list some similar differential carriers, but nothing with the same Jaguar carrier number (SPICER 2006726 part number).
https://www.danaaftermarket.com/

So it looks like we are limited to Jaguar specific rear carriers or rear differentials (built for them by Spicer) ...
which can either be found on the used parts market, or ordered new from Jaguar.

 

Man...been reading up and I really appreciate the work you're doing to try and figure this out. I have a manual '17 as well and would love to get an LSD in mine as well.

 

Update:

• I purchased a used Jaguar F-Type Limited Slip Differential from eBay (from a 2013 380hp S model with Automatic Transmission)..

• I also have a used Jaguar F-Type open differential from eBay (from a 2016 340 hp base model with Auto trans) on my work bench.

First off.. the Open Diff has an obvious "SPICER" name in the casting, and a part number.
The LSD does not have any obvious markings and it only sports some hand written part number references, which makes it appear to be hand assembled and labeled. (unlike the Spicer carrier)
I will remove the ring gear from the LSD carrier (43 teeth) and see if it matches the same bolt pattern as the Open Diff ring gear (41 teeth).
Note: both rear diffs have pinion gears with 13 teeth .. and they look the same... I will get a micrometer on them to confirm their OD.

I did get an e-mail back from QUAIFE in the UK, and they would be interested in taking a look at the Jag F-Type V6 LSD application.
Before I engage them.. it is important to confirm that the two carrier ring gear bolt patterns are the same for the above two parts.
If the 10 bolt ring gear is a common pattern on the above two carriers, then QUAIFE could consider a single part that would accept the stock Jaguar ring gear from the original F-Type.
Note: I have not yet torn into my V6 MT -FA rear diff... so I am not sure if that carrier is any different.. does anyone have the elusive V6 MT -BA rear diff for comparison?

I may also send the Open Diff carrier over to West Coast Differentials to see if they have a LSD carrier that is a match.
West Coast Diff
Thoughts?

@Unhingd @BONESTOCK @jlsthlm
@SinF @airthirtytwo @Cambo@JgaXkr @tbird6 @Richard Chrimes @alphakinase @Dan Wink

pictures:




LSD left cover removed

LSD Hand scribed part number

LSD clutch disks

LSD Ring gear ratio

 

The progress you are making is outstanding. Keep up the good work. I would suggest that you shoot for the 3.31 ratio as the base car will see additional benefit from that ratio.
Caution: Those two 13-tooth pinion gears may look identical, but they are not. They are each cut slightly differently to accommodate the 41 versus 43-tooth ring gears.

 

@Unhingd Thanks for the heads up on the pinion gears. I will take a close look at any differences.
I think the goal of this effort is to develop an alternate 3rd party LSD for V6 Jaguars, so we don't have to wait for used part to pop up on eBay (knowing that an F-Type had to die to donate it organs for the rest of us)
(also applies to F-Pace, XF, and XE applications).

There seem to be two ways to get the LSD performance feature to the Jag enthusiast:

• make a 3rd party LSD carrier available for sale to the Jag owner (plus bolts, cover sealant, etc)
  • the Jag owner would reuse their car's original ring gear and reinstall
• make a rebuilt rear differential with the LSD inside available for a quick swap
  • this replacement rear differential would presumably be based on the common -DA (base 340hp AT version) with 3.15 ratio

The first option seems easy, involving some extra time for the car to be on the lift while the car's rear differential is quickly rebuilt.
But something tells me that a successful outcome is improved (and the car's time on the lift is reduced) if the LSD carrier is pre-assembled and it is pre-aligned inside a replacement differential.
This second option may be necessary if the pinion and ring gears need to be aligned and the backlash set.

Or.. the third option is to have the car's rear differential sent to a rebuild shop and later returned to the user for reinstallation.

 

@Unhingd
I made some measurements on the Open AT differential with 3.15 ratio (41:13 gears, tag -DA) and the LSD AT differential with 3.31 ratio (43:13 gears, tag -AA).
Many things were the same:

• both Ring Gears were 220 mm OD (even though they had different teeth count)
• both Ring Gears had the same 10 bolt pattern and could be mounted to either Carrier, with the same M12 bolts
• both Rear Axle Cases were identical with the same width and bearing races

Some things were different:

• the two Carriers feature different Ring Gear mounting surface heights (as measured from the left most bearing)
• the two Ring Gears were of different thicknesses
• the two Pinion Gears were of different OD (but the same tooth count)

​​​​​​The Ring Gears thicknesses difference was partially counteracted by the mounting height differences, but not totally.
There is still a 1.5mm difference, which, surprise, shows up in the Pinion Gear OD.

I noticed that the Rear Differential Case has an AdvanTEK(TM) mark on it, which means it is from DANA/SPICER.
Their website advertises the DANA 44 AdvanTEK technology which uses a 220 mm OD Ring gear system..
So DANA needs to make a unique Pinion Gear and Ring Gear for each ratio they produce for optimal torque transfer and life...
This design strategy also flows down into requiring a new Ring Gear mating height to align the unique gear combination.

In summary, the only practical path forward to provide a 3rd party LSD solution for the F-Type is to stick with one donor rear differential.
Otherwise, a different LSD Carrier design with unique Ring Gear mounting depth would be required.
It may be possible to specify ring gear shims. But which ratio has the widest spacing? and which has the shallowest spacing?

So .. the most readily available Jaguar AdvanTEK Rear Differential is probably from an XF or F-Pace?? or do we focus on the F-Type AT 3.15 ratio?
I have a 3.15 ratio rear diff (AT base model with -DA tag) that I could ask Quaife to look at and come back with a quote.
They could match the Open Carrier dimensions or get back to us with other options, with an eye to different ring gear mounting heights.

 

Update:
Quaife UK is looking at this application... I have three other firms on my list to ask.
But there are many types of LSD, and whether they engage after a certain speed differential is reached, or if they also engage on reverse torque (engine breaking)...
So some discussion is needed when setting up the characteristics of the LSD for the Jag F-Type.
Some co-workers suggested that LSD tuning can also be a function of tires and driving style. So lots to think about.

In the mean time I also figured out how the Pinion Gear is aligned with the Ring Gear in the AdvanTEK rear differential.
1) the Pinion depth into the housing is set roughly correct
2) the Carrier and Ring Gear can then be moved laterally by way of shims behind the bearings to get the backlash right
3) then there may be an iterative process to get the alignment just right with the use of gear marking compound.
I suspect that having a cover with holes drilled into it would help this process speed up, as it is impossible to measure backlash correctly with the cover on, or backlash needs to be translated into pinion shaft rotation angle or something.

I found a single shim behind each bearing race on the Cover and Axle Housing.
I also identified the bearings as a 32010 type (80mm OD, 50mm ID, 20mm Tkns)
The four shims that I measured on my two differentials were on the order of 1.8 mm thick to 2.4mm thick with an average thickness of 2.25 mm


Bearing and shim on rear axle cover

 

The sequence for all the final drives I've set up (lots of them, but mostly the same kind) is:

1) Set the bearing preload for the carrier. This gives a set of shims for the tapered roller bearings.
2) Set the pinion depth. I had a special tool for the ones I did that made life much easier than an actual measurement.
3) Set the backlash by adjusting the shims between the two sides.

I'm not sure about setting backlash in this case unless there's an access port to get a dial indicator in there. Since the cover also loads the bearings it might be necessary to translate the backlash into pinion rotation as you suggest.

EDIT: Looking at the pictures again I'd say that with only one shim on each side, the combined thickness will set the bearing preload and having a variety of shims that could be paired to reach that thickness would be needed to adjust backlash.

 

The shims that I inspected in my used Dana 44 AdvanTEK rear axles were backing up the Koyo 32010 bearings...
The dimensions were OD = 78 mm , ID = 68.7 mm and various thickness hovering around 2.0 mm

Where does one get such shims? I've looked in all the typical places on the internet and didn't find any obvious sources.
(most sources list by application .. e.g. Jeep Dana 30, or Ford 8.8" rear axle.. not by dimension)

 

My experience was probably about 95% Saab 99/900 and about 5% Saab 96. There were different setups between the two but in both cases the shims were proprietary. Since both were considered dealer serviceable the parts could be obtained at the dealer, although some dealers were unwilling to sell things like factory service tools to independent shops. For the preload shims I had a bunch because I had dismantled numerous transaxles that were not rebuildable. The pinion bearings were usually good for about 125K miles and if left to fail the resultant mess was usually a write-off.

For a unit not considered dealer serviceable I'm not sure where to go. There are shops that specialize in axles that might be able to match them but if they're not compatible with more common axles you might be in for a difficult treasure hunt.

More info on the preload/backlash setup for the curious:

Since the bearings are tapered, the tighter they're squeezed, the harder it is to rotate the carrier. For the ones I worked on, this was specified as force to turn, and measured with a spring scale (fishing scale) with the cord wrapped around a specific part of the carrier. The spec was different for new bearings versus ones with a few thousand miles or more. This gives the total shim stack. I'd typically see 2-4 shims per side. I think they went down to about .002".

By dividing that stack differently between the two sides the carrier could be moved slightly side to side. That's how the backlash is set.

 

Hi @airthirtytwo , I saw in another post thay You managed to do the SWAP, after a bunch of information I stiff confused about the Part numbers, What was Your final letters and ratio?

Thanks a lot!

Diogo

 

@DiogodaSilva86
I think @airthirtytwo settled on the Automatic Transmission, LSD which is Jag part number T2R4000 and has a tag of EX53-4A213-AA, and a 3.31 ratio.
It should swap right in to either a Manual or Auto F-Type.
Note: Base model F-Types with Automatics had the -DA tagged rear differentials with the 3.15 ratio, while the S models got the above LSD with 3.31 ratio.
Note: there is still a question around the Manual axle halves being different than the 2,3,5 Liter Auto axle halves so fitment may need to be confirmed.
(so far I have only found a weight difference between the axles, not a substantive dimension or fit difference, and I will be putting in the LSD in soon on my Manual car)

Update: I am developing a Helical Geared Differential for the F-Type, so you may want to see if that solution fits your goals better.
Look here for updates:
interest-helical-gear-differential-development-266193

 

Here is my updated rear axle file with Tag Numbers, JLR part numbers, and gear ratios.

 

Nice work, I just added that to my Dropbox, if that’s ok with you.
https://www.dropbox.com/sh/wgv3e86yc...glFoM3xOa?dl=0

 

Update:
Welcome back Jaguar Forum Folks.
I have made some headway with both Quaife (UK) and MFactory (Taiwan) in the development of a Helical LSD.
The next step is to finalize the two company's product pricing and initial build quantities.

Group Purchase:
The two companies tend to require a minimum initial build of 10 units. (still in negotiation)
This suggests a group purchase, where each Individual covers their helical LSD carrier purchase price.
Typical pricing for a "large" helical LSD carrier, appropriate for the supercharged V6 cars, is about 1000 USD (800 GBP).

Axle Rebuild Service:
So far I have invested about $3k into surveying Jaguar rear axles, and developing the tools and process to rebuild these units with quality results.
It may be possible for some of you to follow my procedures and rent my tools, but I would prefer to offer my services to rebuild the rear axles for you.
(I have also learned how to best ship rear axles domestically, and internationally... a story for an other day.)

Rebuild Logistics:
The tricky part is how the Helical LSD carrier gets mated with an appropriate rear axle. I see two possible sequences:
1. Individual removes and ships their Jag's rear axle to me for rebuild. A bit later they receive their rebuilt rear axle.
2. I procure an appropriate used axle (for a fee+core charge), rebuild it and ship to the Individual. Later the Individual sends their old rear axle back for a core charge refund.

Option 1 requires the Individual to remove and package up their old axle and wait for some turn-around time with their Jag out of commission.
Option 2 requires some additional financial outlay by the Individual, but the Jag's down time is minimized and the core charge will be refunded.

I favor Option 2, which removes time pressure from the equation, and minimizes Jaguar down time.

Refinements:
I have developed a way safely media blast the exterior of the axle and apply a self etching primer and gloss black top coat.
(other colors available :-)
I have also invested in a custom aluminum tag, identifying the rear axle as a "Helical LSD."
This tag will be located next to the drain plug, so it is easy to see the unit's rebuild date, gear ratio, oil type, and original Jaguar tag number.

Jaguar Applications:
The helical LSD solution in development is known to work with the below Jaguar applications.
Jaguar F-Type V6S Auto, friction LSD, ratio 3.31, tag: EX53-4A213-AA fiction LSD's wear out and can cause other internal damage
Jaguar XE V6 Auto, open diff, ratio 3.23, tag: GX73-4A213-JA has yoke dampener (superfluous)
Jaguar F-Type V6 Auto, open diff, ratio 3.15, tag: EX53-4A213-DA most plentiful application

Other probable fitments:
Jaguar F-Type V6S Manual, friction LSD, ratio 3.31, tag: EX53-4A213-BA should be the same ring and pinion gears as the -AA
Jaguar F-Type V6 Manual, open diff, ratio 3.31, tag: EX53-4A213-FA should be the same ring and pinion gears as the -AA

I am getting a bit busy with a move from VT to RI, so I don't know if I can get this LSD finalized before mid-summer.
See my other thread on a custom flywheel and clutch development.


Summary of key dimensions and tolerances

left-to-right: used, media blasted, primed & painted

primed and painted, with custom tag next to drain hole

 

watching, I would be interested in purchasing if I don't do the OEM LSD swap first.

 

@addict Thanks for your interest.
There is a big improvement in spirited driving between an open diff, and an LSD.
The traction provided on marginal or mixed surfaces is greatly improved, and the vehicle tends to track straighter.
The real question is whether to install a Friction based or a Helical based LSD (also called "Torsen").

OEM Friction LSD:
The OEM Jaguar LSD found in many V6 S model F-Types, is a Friction unit with 4 clutch plates, which wears during use.
It requires frequent oil changes as the friction disc material spoils the gear oil and breaks down the friction modifiers.
The unit I purchased used lasted 40 k miles before the friction disks wore out, and there is no rebuild kit available ... have to buy a replacement rear axle from Jaguar.
There is also the issue of the friction LSD locking the two rear axles during activation, rather than allowing for torque splitting between the two rear axles.
Some friction LSD's do have the ability to be "tuned" to meet demanding race applications (in both acceleration and deceleration), but alas.. no options for the Jaguar OEM LSD.

New Helical LSD:
The helical LSD under development is maintenance free, smooth acting, and splits the torque available between the rear axles.
The unit I am commissioning will have a Torque Bias Ratio of about 4:1, which is great for street, and occasional track events.
The rear axle is not modified during the conversion, so the helical LSD will literally be a bolt in replacement.... you can always go back to stock.

What other concerns do you have?