6MT Centre Differential Rebuild Project

[BillyCorgi]

Just to clarify....
Are you after a centre differential for a 5MT or 6MT?

[Daemos]

Just to clarify....
Are you after a centre differential for a 5MT or 6MT?

6MT centre differential is what I am looking for. However, I am looking for something that has more lock than the 4KG but not too much to sacrifice road manners and low speed day to day stuff.

[BillyCorgi]

There are higher viscosity silicone fluids available.
There effect of an alternative viscosity fluid on the transfer torque through the differential would be guesstimation and trial & error (hit & miss?)
Then their final effect on the handling of your vehicle then follows a similar trial & error process until the transfer torque achieved meets your liking?
How the "level of liking" is achieved, by what process or subjective driving test, is undetermined at this point in time.
This could possibly mean taking the diff in and out a few times, rebuilding it, until it hits your sweet-spot.

The "fill-rate" for any alternative grade fluid could only presently be maintained as that the same for the standard initial fill, as that presently is all we have to go by.

I do not have numerous cores available and really need all of them back after exchange.

Suggest that you find a rotten 6MT core (so to speak) for your purpose.
Maybe put an appeal out through the forum to see if anyone had an old core for your needs. Else, contact some workshops to see if they have some dead cores.
Let me know what you think so far.

[Daemos]

Thanks for the reply. I'll see what I can find, hopefully I can find something. I'd probably want something in the 8-10kg range.

[bigBADbenny]

Sent u a PM, Daemos.

[BillyCorgi]

Here awaiting your replacement Centre Differential requirements

[BillyCorgi]

OKAY, Time for an Update.

Cliffo3rb contacted me about a Centre Differential Rebuild on Friday night.
The Centre Differential was delivered to me bright and early on Saturday morning.

The diff was pulled apart Saturday evening and was full of the usual black tar and encrusted coating of the overheated silicone typical of a binding Centre Diff.
Here it is after its first wash/clean to remove all the silicone fluid.


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Next step after an air dry overnight was a second wash in detergents to remove any traces of oils.


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The reassembly process next is the reverse of the taking apart procedure.
Starting to fill the diff with new silicone fluid.


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Add plates.....


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Add more plates.....


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Let the fluid settle and locate Internal Thrust Washer.....


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Then seal the unit it up and put on Circlip.....


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There are some steps that have been very much over simplified and some other steps in the assembly process deliberately omitted as they are part of the Corgi IP.
However, there you are.
Cliffo3rb will have his Centre Differential back on Monday to reinstall in the gearbox of the Garage Queen!

[Brunsy3.0]

Pretty efficient now. Smashing it out
Looks like you got it sorted
Top job as always

[BillyCorgi]

Top job as always

Thank you Mr Brunsy.
As you were an important part of this project, your existing centre diff will be supported by me for the lifetime of your vehicle.
Cheers!

[Brunsy3.0]

Top job as always

Thank you Mr Brunsy.
As you were an important part of this project, your existing centre diff will be supported by me for the lifetime of your vehicle.
Cheers!

Hopefully wont need another rebuild/replacement in its lifetime although seems about the 150k interval haha
Appreciate it though

[BillyCorgi]

UPDATE

(1) I have core ready to ship with 24 hours notice.

(2) There is now stock of 1,000,000 cSt silicone fluid.
Specials can now be produced with higher kg.F rating.

The silicone fluid viscosities can be blended by weight to produce a kg.F specification of your choosing.

(3) Why do the Centre Differentials fail?
Due you the effects of excess heat and age, the Silicone Fluid undergoes a process called "gelation".
This causes certain portion of the silicone fluid to go "gelly-like".
In this state, once the diff heats up and the silicone fluid become warm, the "gelly" prevents the clutch plates from slipping past each other as they normally would and the differential "binds".
The operation of the viscous coupling (and therefore the operation of the Centre Differential) is restored by fresh fluid.

[BillyCorgi]

8th May 2016
6MT Centre Differential Available Ready to ship
CW38913AA112

[bigBADbenny]

Totally sick! Love the option to upgrade, tempted!!!

[BillyCorgi]

Hi All,

Been a while since an update has been posted.
Have not done many 5MT Centre Differentials, however have done a couple in the last two weeks.
The first one received (exchange) the unit that originally came out of Junior #2's Liberty Wagon. This was the unit that kicked off this centre differential rebuild project.

The second came from country Queensland.
Rebuilding the customer's own Centre Differential for them.
May I say that I have never (never, ever, ever) seen a Centre Differential Viscous Coupling like this.
Rather than pulling it apart and finding the clutch discs swimming in a foul smelling sticky viscous silicone fluid, it was SOLID. Not a drop of liquid to be found.
The diff would have been seized solid.
The clutch discs literally had to excavated out of the solid muck.
You can see the solid parts in the bottom of the pan.

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The Clutch Disc Pack was ruined were not able to be rebuilt.
A replacement Clutch Disc Pack was required.

I do not know how the car was driven?

[tom_kauf]

WOW