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CSBrisie
30th July 2018, 09:06 PM
All, quick query: on L494, is the rear e-diff standard on the Dynamic Pack?
I'm looking at purchasing a HSE SDV8 Dynamic....if that gets e-diff standard?
cheers

Geedublya
31st July 2018, 04:42 AM
All, quick query: on L494, is the rear e-diff standard on the Dynamic Pack?
I'm looking at purchasing a HSE SDV8 Dynamic....if that gets e-diff standard?
cheers

The rear diff is required for the torque vectoring used in the Dynamic as far as I know. All the L494 Dynamics I looked at had an e-diff.

Gregz
31st July 2018, 11:03 AM
The rear diff is required for the torque vectoring used in the Dynamic as far as I know. All the L494 Dynamics I looked at had an e-diff.

Agreeing with Geedublya... from the 2017 specs for instance, the Dynamic Response / TR2-DP / Torque Vectoring indicate that it has the rear e-diff

142735

CSBrisie
31st July 2018, 10:24 PM
Thanks All 👍

Ausmate
13th October 2020, 09:59 PM
Agreeing with Geedublya... from the 2017 specs for instance, the Dynamic Response / TR2-DP / Torque Vectoring indicate that it has the rear e-diff

142735

any chance this can be retrofitted to the HSE version of the RRs ?

Graeme
14th October 2020, 06:33 AM
Retro-fitting an e-diff requires finding an e-diff with the correct ratio, obtaining a suitable e-diff control unit, obtaining or fabricating the wiring harness to connect the e-diff to the control unit, connecting the control unit to 30A power, ignition, earth and to the appropriate can-bus, access to a diagnostic tool to re-configure the CCF to enable the e-diff and if the control unit didn't come from the same vehicle as the e-diff then access to a diagnostic tool to instruct the control unit to calibrate the e-diff. A LR dealer's diagnostic tool can be used to calibrate but is unlikely able to change the required CCF settings.

Ausmate
14th October 2020, 10:44 PM
Retro-fitting an e-diff requires finding an e-diff with the correct ratio, obtaining a suitable e-diff control unit, obtaining or fabricating the wiring harness to connect the e-diff to the control unit, connecting the control unit to 30A power, ignition, earth and to the appropriate can-bus, access to a diagnostic tool to re-configure the CCF to enable the e-diff and if the control unit didn't come from the same vehicle as the e-diff then access to a diagnostic tool to instruct the control unit to calibrate the e-diff. A LR dealer's diagnostic tool can be used to calibrate but is unlikely able to change the required CCF settings.

the GAP tool will modify the CCFs the difficulty is matching the ediff module, to the ediff motor and matching that to the ratio of the Diff that in my l494 RRs.

love the LAMS kit btw, nice job.

Graeme
15th October 2020, 07:11 AM
If the GAP tool supports your CCF then even if it doesn't currently provide the calibration feature, time permitting GAP may be able to provide the feature, possibly as a special, pre-release update for your tool as GAP did for my L322.

Calibration is an inbuilt function of the control unit whereby the e-diff is operated to its minimum and maximum engagement travel so that the control unit can establish its operational criteria. Calibration requesting is a standard LR diagnostic tool function, achieved by simply sending the appropriate command to the control unit.

If you find an e-diff of the correct ratio and, which LR often vary depending on the engine fitted, then hopefully you could also get the control unit. What is your year model and what engine? I only have details for MY13 L405 for which a different e-diff part number is listed depending on whether the engine is the 4.4 diesel (LR039512) or 5.0 SC petrol (LR039513) which implies different ratios. I note that the e-diff was available with the 3.0 diesel but possibly not for MY14 but certainly later. Also the e-diff has different part numbers depending on whether torque vectoring was employed, so lots to consider when selecting an e-diff. Hence an e-diff from the same MY and engine as your vehicle would be safest.

I was fortunate with my L322's wiring harness in that the external wiring from the main harness to the e-diff is a distinct harness, albeit in 3 different configurations depending on whether an e-diff and a fuel-fired heater were fitted, so I purchased the one that supported both. Internally I had to make my own harness between the connector on the main harness and the control unit and purchase connector shells and pins as while the control unit was supplied with connectors, the wires were too short to be usable. Fortunately again the connector on the main harness is the same as one of the suspension ecu's that I use for my Llams kits so it was easy to add the extra pins to the connector. D3/D4 e-diff harness is incorporated in the main harness if an e-diff was fitted otherwise no e-diff harness at all, which therefore would require a direct harness between the e-diff and control unit to be made. I don't know if your L494 has a distinct e-diff harness section like the L322 but could be determined by looking at a L494 or L405 with an e-diff, following the harness from the e-diff to inside the vehicle.

It sounds as though you're making good use of Llams.

Graeme
15th October 2020, 12:27 PM
Electronic torque management appears as though it may have been a standard feature for all L405 and L494 that were fitted with an e-diff. Enabling a retro-fitted e-diff in the CCF might enable ETM or ETM might have to be separately enabled. ETM uses both the e-diff and brakes to improve steering while cornering by managing e-diff slip and using braking to make the vehicle turn more easily. ETM can be ignored as factor when considering a donor vehicle as your vehicle without an e-diff hasn't been able to use it. The different part numbers were for a motor and housing change but unrelated to ETM as ETM was employed on vehicles for both the earlier and later part numbers. MY17 e-diffs may be different or perhaps just that the references that I found didn't consider post MY16.

Ausmate
15th October 2020, 06:49 PM
If the GAP tool supports your CCF then even if it doesn't currently provide the calibration feature, time permitting GAP may be able to provide the feature, possibly as a special, pre-release update for your tool as GAP did for my L322.

Calibration is an inbuilt function of the control unit whereby the e-diff is operated to its minimum and maximum engagement travel so that the control unit can establish its operational criteria. Calibration requesting is a standard LR diagnostic tool function, achieved by simply sending the appropriate command to the control unit.

If you find an e-diff of the correct ratio and, which LR often vary depending on the engine fitted, then hopefully you could also get the control unit. What is your year model and what engine? I only have details for MY13 L405 for which a different e-diff part number is listed depending on whether the engine is the 4.4 diesel (LR039512) or 5.0 SC petrol (LR039513) which implies different ratios. I note that the e-diff was available with the 3.0 diesel but possibly not for MY14 but certainly later. Also the e-diff has different part numbers depending on whether torque vectoring was employed, so lots to consider when selecting an e-diff. Hence an e-diff from the same MY and engine as your vehicle would be safest.

I was fortunate with my L322's wiring harness in that the external wiring from the main harness to the e-diff is a distinct harness, albeit in 3 different configurations depending on whether an e-diff and a fuel-fired heater were fitted, so I purchased the one that supported both. Internally I had to make my own harness between the connector on the main harness and the control unit and purchase connector shells and pins as while the control unit was supplied with connectors, the wires were too short to be usable. Fortunately again the connector on the main harness is the same as one of the suspension ecu's that I use for my Llams kits so it was easy to add the extra pins to the connector. D3/D4 e-diff harness is incorporated in the main harness if an e-diff was fitted otherwise no e-diff harness at all, which therefore would require a direct harness between the e-diff and control unit to be made. I don't know if your L494 has a distinct e-diff harness section like the L322 but could be determined by looking at a L494 or L405 with an e-diff, following the harness from the e-diff to inside the vehicle.

It sounds as though you're making good use of Llams.

Great info Graeme , Thankyou. I have a My16 RRs L494 with the 3.0 v6 twin turn diesel motor. I’m lacking part breakdown for the RRs to,work out exactly which ediff motor And ediff module is required for this particular car. The ediff Module I’ve been chasing Is LR083860 but I’m sure is that is actually correct.

Graeme
15th October 2020, 08:31 PM
That control unit part number is listed for the RRS VIN DA786425 which is in the MY13 range which is the original L320 RRS and also for MY13 L405 and some D4s and the L322. LR034525 appears to be the one that you need.

Assuming that you're looking to source a used e-diff, I suggest that you get both the complete e-diff and the control unit out of any pre MY17 (to be safe) 3.0 V6 L494 or probably L405 although you will still need to confirm that it has the same diff ratio as your vehicle. You could do this by checking that the front diff part numbers for the 3.0 V6 are the same whether the rear is open or e-diff. My copy of Microcat 2012 lists only 1 front diff for the MY13 L405 3.0 V6 (LR039597 now superseded many times so perhaps still current) but no rear e-diff is listed for this vehicle which could be an error in the catalogue but the 3.0 V6 in your MY16 L494 could use a different ratio anyway.

The e-diff motor that is fitted to the e-diff will be the correct one, just be sure that its connector isn't damaged.

Ausmate
16th October 2020, 11:42 AM
That control unit part number is listed for the RRS VIN DA786425 which is in the MY13 range which is the original L320 RRS and also for MY13 L405 and some D4s and the L322. LR034525 appears to be the one that you need.

Assuming that you're looking to source a used e-diff, I suggest that you get both the complete e-diff and the control unit out of any pre MY17 (to be safe) 3.0 V6 L494 or probably L405 although you will still need to confirm that it has the same diff ratio as your vehicle. You could do this by checking that the front diff part numbers for the 3.0 V6 are the same whether the rear is open or e-diff. My copy of Microcat 2012 lists only 1 front diff for the MY13 L405 3.0 V6 (LR039597 now superseded many times so perhaps still current) but no rear e-diff is listed for this vehicle which could be an error in the catalogue but the 3.0 V6 in your MY16 L494 could use a different ratio anyway.

The e-diff motor that is fitted to the e-diff will be the correct one, just be sure that its connector isn't damaged.

Thanks Graeme, that’s helpful.

I've found a a car one suburb away from me that might fit what I’m looking for. He has asked for a parts list but I’m having trouble finding a site that can give that to me. He also mentioned the ediff motor is the same regardless of the rear centre diff ratio but I doubt that’s correct.
If I’m reading this correct I need;
Ediff motor from the rear diff - part number ?
Ediff module - part number LR034525
Ediff harness between them.
Would you know of a site I can put my vin into and also a vin of a HSE Dynamic v6 diesel car that can show me the different part numbers ?

101RRS
16th October 2020, 12:46 PM
So you have found sound someone wrecking a L494 RRS with the Dynamic Pack? That would be a lucky find.

This link has a project to convert a D4 to install the genuine e diff - not all that easy - yes a D4 not a L494 but gives an idea of whats involved.

LR4 Factory Locker Swap | Expedition Portal (https://expeditionportal.com/forum/threads/lr4-factory-locker-swap.218167/)

Graeme
16th October 2020, 02:38 PM
The e-diff motor is indeed the same regardless of the diff ratio as the motor turns the internal mechanism to apply pressure on the clutch plates, nothing to do with the drive itself. Don't use an e-diff motor from a L320 or D4 etc as it appears to have been revised for use with ETM. Just get the whole diff housing complete with its motor if the e-diff has the same ratio as your vehicle. IIRC the ratio is stamped on a tag on the diff, well it was for mine.

I'll see what I can discover about the 3.0 V6 front diff ratios but a visit to your local LR dealer parts dept with your VIN and the proposed donor's VIN to check if the front diff is the same part number for both vehicles.

I retrofitted an e-diff to my L322 so have some experience with this task.

Graeme
16th October 2020, 02:46 PM
Both my original open diff and the acquired e-diff had original paper labels attached that showed the ratio.

Get a much of the e-diff and control unit wiring that you can, back to other connectors if possible.

Graeme
17th October 2020, 05:18 PM
Whilst it appears that somewhere between the start of MY2016 and the start of MY2017 the L494/L405 front diff was changed such that the later diff isn't suitable for the earlier vehicles and vice versa, L405s and L494s fitted with the TDV6 diesel have been fitted with 3.21:1 ratio front and therefore rear diffs since the beginning of the model and at least up to the end of MY17. Hence an e-diff from MY17 or earlier will have the same ratio as your vehicle and one from MY18+ may still have the same ratio but would need to be verified.

Edit: The rear diff is also reportedly changed for 2017 models so perhaps there was a ratio change. With your vehicle MY16 I'd be looking for a sticker on either the front or rear diff of your L494 and a sticker on the front or rear of the proposed donor to confirm the ratios rather than rely on supplier web-sites.

Ausmate
19th October 2020, 03:07 PM
Whilst it appears that somewhere between the start of MY2016 and the start of MY2017 the L494/L405 front diff was changed such that the later diff isn't suitable for the earlier vehicles and vice versa, L405s and L494s fitted with the TDV6 diesel have been fitted with 3.21:1 ratio front and therefore rear diffs since the beginning of the model and at least up to the end of MY17. Hence an e-diff from MY17 or earlier will have the same ratio as your vehicle and one from MY18+ may still have the same ratio but would need to be verified.

Edit: The rear diff is also reportedly changed for 2017 models so perhaps there was a ratio change. With your vehicle MY16 I'd be looking for a sticker on either the front or rear diff of your L494 and a sticker on the front or rear of the proposed donor to confirm the ratios rather than rely on supplier web-sites.

Thankyou.

In NZ I have found a Sport L494 SDV8 with the locking diff as std and is a MY16.5, vin SALWA2JE8GA586201

The part number from this VIN lead us to the following;

EModule - ECU
LR057232 Superseeded to -> LR083860

eDiff
LR058406 Superseeded to -> LR070147

Loom
LR075618 Superseeded to -> LR089079


Any thoughts ? as it seems to fit the spec required. cheers

Graeme
19th October 2020, 04:02 PM
The SDV8 has higher ratio diffs so its e-diff is unsuitable for your TDV6.

LR075618 appears to have been superseded by LR089679.

The harness picture that I found appears to have connectors very similar to the 2 that connect to the ediff. If you're lucky its 4 large connectors may connect to existing connectors in the main harness in which case other connectors may also exist for the control unit. You might want to go looking for the 4 black connectors and the control unit connectors (black, yellow and purple of the same design if same as earlier vehicles) in the rear of your vehicle. One or more of the 4 larger black connectors may already be in use.

Ausmate
19th October 2020, 08:11 PM
The SDV8 has higher ratio diffs so its e-diff is unsuitable for your TDV6.

LR075618 appears to have been superseded by LR089679.

The harness picture that I found appears to have connectors very similar to the 2 that connect to the ediff. If you're lucky its 4 large connectors may connect to existing connectors in the main harness in which case other connectors may also exist for the control unit. You might want to go looking for the 4 black connectors and the control unit connectors (black, yellow and purple of the same design if same as earlier vehicles) in the rear of your vehicle. One or more of the 4 larger black connectors may already be in use.

Thanks again. I will try and have a look.

I might be missing something but the tag on the back of my car is SDV6 which I thought was the v6 version of the SDV8. I didn’t think I had a TDV6. Thoughts ?

Graeme
20th October 2020, 06:05 AM
TDV6 or SDV6, it is still the V6 diesel to which a lower ratio diff is fitted presumably because the engine doesn't have the torque at low revs that the V8 diesel does.

Ausmate
21st October 2020, 12:10 PM
Both my original open diff and the acquired e-diff had original paper labels attached that showed the ratio.

Get a much of the e-diff and control unit wiring that you can, back to other connectors if possible.

I missed this - I'm running currently an Open Diff and I require a Diff change to get the ediff. I was confused by thinking I could fit an ediff motor to the diff that I had already. Thanks for the clarification - Will continue searching.

101RRS
21st October 2020, 01:28 PM
Oh dear - you really need to a lot of research before embarking on such a project - even basic research would have shown whats in the diff housing is vastly different between the open and ediffs - not friction plates in the open diff - heaps of friction plates in an e diff.

This is the e-diff of a D3 - you can see the plates and the motor and this will be basically the same for a later RRS.


165589

Did you review the link I put up earlier on the experiences of someone actually doing it in a D4?

Ausmate
21st October 2020, 09:22 PM
Did you review the link I put up earlier on the experiences of someone actually doing it in a D4?

I did, saw it, understood parts of it, but undeterred so I’m pressing on.
If I learn a bit along the way then that’s the fun of it.
Apologies upfront if I’m wasting you time.

Graeme
22nd October 2020, 05:48 AM
My concern is that you'll start buying parts then not complete the task.

Here's my retrofit thread.

Rear e-diff retrofit to MY12 4.4 TDV8 (https://www.aulro.com/afvb/l322-range-rover/238989-rear-e-diff-retrofit-my12-4-4-tdv8.html)

101RRS
22nd October 2020, 11:56 AM
Yes that is my concern - was already looking at buying parts from different models that may not fit and not even understanding the physical differences between normal and e diffs (ie assuming the friction plates are in the open diff and only need the motor).

Now I think this is a worthwhile project if you are so inclined but a lot of research and learning of the systems are needed before even going out and looking for parts.

I accept that coming here and posing questions is a great way to start the research process but hasten slowly comes to mind.

Now I dont know - but before I embark on the e-diff route, I would be checking to see if the D3 front and rear diffs fit in your much later vehicle as ARB diff locks will fit. Also, I would look at whether you really need your ediff linked into your car's systems - the motor just changes the amount of friction at the plates so manually applied voltages may be able to be applied to the diff motor - so if you apply the unlocked voltage to the motor, does the diff go unlocked, same with a mid range voltage and the same at the fully locked voltage - does it actually lock the diff?

I don't know but would seem a simpler solution that a complex fully integrated solution. There are options.

Garry

Graeme
22nd October 2020, 03:02 PM
Sourcing the correct ratio diff is the biggest hurdle, with the other aspects rather trivial although one must fit an appropriate control module for the vehicle. Integrating with the rest of the electronics is the least of concerns because the other modules already allow for an e-diff if the CCF shows that one is fitted.

The L405/L494 diff housing is quite different to the D3/D4/L320 housings and both early and later L322 housings.

Ausmate
22nd October 2020, 06:06 PM
Sourcing the correct ratio diff is the biggest hurdle, with the other aspects rather trivial although one must fit an appropriate control module for the vehicle. Integrating with the rest of the electronics is the least of concerns because the other modules already allow for an e-diff if the CCF shows that one is fitted.

The L405/L494 diff housing is quite different to the D3/D4/L320 housings and both early and later L322 housings.

Thanks Gents, Haven't bought anything and I will continue research.

My plan currently is to look for a MY16 SDV6 or TDV6 'REAR AXLE ACT LCKG DIFF W/TVBB' to Replace my 'REAR AXLE OPEN DIFF' and hopefully from that L494 grab the ediff ECU and cabling harness.

Have yet to find one of these rare beasts but I did find a MY14 L494 with what I needed.

Regards

Ausmate
30th October 2020, 06:27 PM
With much research I've been chasing the following part numbers for the rear locking diff (REAR AXLE ACT LCKG DIFF W/TVBB);

LR070145 or DPLA4A213FC which have a diff ratio of 3.21:1

The RDCM ( Rear Differential Control module ) ediff module or ECU is required also which links into the ISCM Integrated Suspension Control Module which controls the Air Lift and Continuous Variable Damping which I already have.

See attachments more info.

the Rear diff rations are;


Reduction ratio:



Vehicles with 4.4L diesel engine
2.73:1


Vehicles with 3.0L diesel engine
3.21:1


Vehicles with 5.0L supercharged petrol engine
3.31:1


Vehicles with 3.0L supercharged petrol engine
3.73:1


Vehicles with 3.0L diesel hybrid engine
3.21:1

Graeme
30th October 2020, 08:32 PM
If buying a reconditioned diff, you need to check if the diff motor is included. LR changed from allocating a number to the diff including the motor to a different part number for the bare diff, ie without the motor. LR070145 supersedes an earlier number so technically might not include the motor, but would expect to if sourcing from a wreck.

Have you identified the RDCU part number for MY14+ RRS / L405?

A friend has recently bought a MY14 RRS fitted with the Dynamic Pack which includes the e-diff for "torque vectoring" which therefore should be compatible with your MY16.

Ausmate
31st October 2020, 12:02 AM
If buying a reconditioned diff, you need to check if the diff motor is included. LR changed from allocating a number to the diff including the motor to a different part number for the bare diff, ie without the motor. LR070145 supersedes an earlier number so technically might not include the motor, but would expect to if sourcing from a wreck.

Have you identified the RDCU part number for MY14+ RRS / L405?

A friend has recently bought a MY14 RRS fitted with the Dynamic Pack which includes the e-diff for "torque vectoring" which therefore should be compatible with your MY16.

thanks for the response. The diff I’ve found and purchase includes the diff motor. $1300 landed and from the UK originally out of a 2016 HSE dynamic SDV6. I thinks it’s been out in the weather as it doesn’t look that great.

I’ve found the harness and RDCU at a few different places. Stag4x4 in NZ has them for NZ$1500 and I think they are the same for the TDV8 and SDV8 but no I can’t find the part numbers on topix.

Ausmate
31st October 2020, 12:05 AM
A friend has recently bought a MY14 RRS fitted with the Dynamic Pack which includes the e-diff for "torque vectoring" which therefore should be compatible with your MY16.

Is he parting out the MY14 RRS ? If so would be interested in buying the harness and RDCU. Cheers

Graeme
31st October 2020, 05:46 AM
The RDCU will be the same regardless of the engine but it appears that it will need to be from no earlier than MY14 and possibly no later than MY16 due to the part numbers not superseding to the the MY17 number. Earlier than MY14 appear to only be suitable for up to MY13, including the L405 which makes me think that torque vectoring might not have been available on the MY13 L405.

Ausmate
4th November 2020, 11:33 AM
The RDCU will be the same regardless of the engine but it appears that it will need to be from no earlier than MY14 and possibly no later than MY16 due to the part numbers not superseding to the the MY17 number. Earlier than MY14 appear to only be suitable for up to MY13, including the L405 which makes me think that torque vectoring might not have been available on the MY13 L405.

The RDCU I grabbed then might be the wrong one. I was advised the RDCU was the same with a different flash version for the different cars. The One I grabbed is a "L494 2013- on rear active diff control module ecu LR086488" from a 2018 face lifted car. The part number on the unit is HY32-4C117-AD and I have looked at a lot of these from 2016 through to 2019 and all have the same part number.

Gap advised they can flash the unit to whatever version we need to suit the vehicle. The harness is being difficult to source.

Also I was advised the locking diff that I purchased, that actually comes with the 12v locking motor, is un-serviceable but on Topix I found a method to pull apart the diff and replace pinion seals etc.

Graeme, where to you find your part number references ? Topix is really letting me down here.

Graeme
4th November 2020, 08:54 PM
I recently spotted a reference to a genuine L494/L405 rebuild kit too.

GAP provided a reflash for my ACC radar unit unit when it was discovered that its firmware was for another vehicle - a Jag IIRC.

I get my part numbers from Microcat 2012 version which includes the MY13 L405, but nothing later.

Ausmate
12th November 2020, 03:48 PM
I recently spotted a reference to a genuine L494/L405 rebuild kit too.
GAP provided a reflash for my ACC radar unit unit when it was discovered that its firmware was for another vehicle - a Jag IIRC.
I get my part numbers from Microcat 2012 version which includes the MY13 L405, but nothing later.

Thanks,

GAP have said getting a flash to suit the RDCM for my car shouldn't be a problem.
The eDiff turned up yesterday from the UK - Obviously paid too much for freight cause it took only 1.5 week to get here. I've taken the diff to Diff Lappers and have asked Carl to pull it apart, identify the ratio for 3.21 (SDV6) and advise its condition.
166077

I also have the RDCM from a 2016 UK L494 as well thats arrived.
I'm sure the harness is in the car to support the eDiff as I remember when fitting the T harness for LAMS there were a few other connectors sitting spare. The RDCM mounts, according to TOPIZ, those spare connectors were directly below where the RDCM mounts into the rear RHS side trunk cavity. Have also traveled to a wrecked L494 and it has spare connectors as well. See below for the mounting location.
166079166078


The Diff will be installed early December and I've identified the following CCF changes that I think will be required;



Rear Differential Type = "Rear Diff type ( Controlled by RDCM )"
Locking Gear axel differential = "Rear Differential Lock-Up is fitted"
Electronic Differential Participating = "Yes"
Limited Slip Differential = "Fitted"

Not sure about item 4 and haven't found any for the 4x4i screen changes to show the rear diff locker icon on screen graphically so I'm hoping that will just appear once calibrated.

166080

Hopefully this will come together nicely.

Regards and thanks for your assistance Graeme

Graeme
12th November 2020, 06:19 PM
Your attachments won't open.

The ratio would easily be checked by marking a driveshaft spline then counting the pinion turns to get the mark back to the starting point. Whilst only counting the teeth on the pinion and crown wheel will allow the precise ratio to be determined, the other ratios used are sufficiently different to be able to determine if approximately 3.2 turns of the pinion results in a full turn of the crown wheel. No need to check the other side too unless turning the pinion only turns 1 side indicating that there is an internal problem.

Ausmate
9th December 2020, 10:19 PM
Your attachments won't open.

The ratio would easily be checked by marking a driveshaft spline then counting the pinion turns to get the mark back to the starting point. Whilst only counting the teeth on the pinion and crown wheel will allow the precise ratio to be determined, the other ratios used are sufficiently different to be able to determine if approximately 3.2 turns of the pinion results in a full turn of the crown wheel. No need to check the other side too unless turning the pinion only turns 1 side indicating that there is an internal problem.

Apologies Re attachments. I thought following the right process would drop them in but I can’t find where to repost with the correct attachments. Anyway, an update.

Yesterday the 2016 diff with locking motor was trail fitted into the RRs but the left (?) hand half shaft was the wrong size ie. the two half shafts from the factory open diff didn’t suit the new locking diff. Very disappointed. I can’t find where the different half shaft can be ordered and I’m thinking perhaps my mechanic has it wrong but have yet to speak to me Re the install. I get the feeling he is avoiding me.

Graeme
10th December 2020, 06:31 AM
LR034535 is the original part number for the MY13 L405's left half-shaft when e-diff fitted so likely the same for your L494. The L405's right half-shaft is the same for both diffs.
I hadn't previously considered that the e-diff shafts might be different as my L322's are the same for either diff. The L322's open diff housing is extended on the left side in the same was as the D3/D4 open diff housing is extended but the L405/L494 open diff housing stops short thus requiring a longer half-shaft for the open diff.

Graeme
10th December 2020, 08:16 AM
E-diff and open diff.

Ausmate
13th December 2020, 09:11 AM
E-diff and open diff.

Thankyou - That’s them, I require a LR073345 $1090 inc freight to Brisbane. Rear left hand half shaft.

The wiring loom isn’t in the car so we’re trying to source at least the end connectors to make one up. Expensive to remove and refit a rear diff - $900 in labour each way 😮

Ausmate
20th April 2021, 03:51 PM
Trying to upgrade an open Diff to an eDiff for a 2016 RRs HSE.

Things to Know;


Topix subscription doesn't have part number for our Australian Region. They want you to deal with the dealers.
Within the VIN the letters GA, HA etc nominate the years of manufacture and for the RRs August each year is the cut off.
I needed to find a RMCM ( Rear Diff Control Module), Wiring harness and eDiff from another donor GA vehicle. Stag 4x4 in NZ had the harness and the correct RDCM.
The RDCM has different connectors from 2016 to 2017 so harness and RDCM should be sourced together.
I have yet to see if the GAP IID Tool will program the CCF for the car to get the diff working but have since bought a VCI tool from JLR to use the factory tool SDD.
LR073345 Rear left hand half shaft is required for the eDiff to fit correctly.
If you purchase an eDiff thats been sitting for a while get the drive shaft input seal replaced.


This eDiff upgrade is not for the faint hearted.

Cheers

Ausmate
31st October 2021, 09:19 PM
Hi all,

This is the end of a long journey.

Turns out the eDiff telemetry is provided by the CHCM ( body control module ) which uses Active Roll Control and the ABS module but without ARC the eDiff won’t function.

I’m either going to fit the ARC system to my 2016 RRs L494 GA HSE or try and control the rest Diff control module or eDiff directly.

ARC is offered standard on the HSE Dynamic and above RRs.

Regards.

Bails
10th November 2021, 08:51 AM
All, quick query: on L494, is the rear e-diff standard on the Dynamic Pack?
I'm looking at purchasing a HSE SDV8 Dynamic....if that gets e-diff standard?
cheers
All SDV8's have the Dynamic transmission. In Australia the dynamic pack was a paint option??

Pedro_The_Swift
14th November 2021, 12:25 PM
My 16.5 doesnt have the red rear badging, the only way I can tell is the off road program graphics have two padlocks?

Graeme
14th November 2021, 03:15 PM
You could always take a peek at the diff itself. Even if you can't see the top of the diff to see if a lock motor is fitted, looking forward from underneath the rear the left side of an open diff is flat with a long spigot to the driveshaft whereas an e-diff bulges away from the line of bolts as it houses the clutch pack and has quite a short spigot to the driveshaft.