Thread: Discovery 3 e-diff

Originally Posted by wrinklearthur

Hi All

To me it looks like the mechanism is a very clever arrangement, that has increasing amounts of controlled slippage until it fully locks..

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I have noticed that the diff lock lights up with 3 little arcs on the screen. Is this what you are referring to ?
Seems that when one is lit up then that maybe has a little slip, the second one maybe a little less slip, then the full on red display is fully locked. Book does not tell me anything about this.

It makes sense to me to not slip as slipping could wear out the clutch plates quite quickly. The same effect as variable slippage could be achieved by varying the percentage of time the diff is locked. A stepper motor would allow very quick and thus short-duration locked and unlocked times.

Ok... Definitive answer time!

The e-Diff does NOT lock.

When wound up to max, you can still turn an e-Diff but you would require a force of approx 30,000nm!!

M

Originally Posted by camel_landy

Ok... Definitive answer time!

The e-Diff does NOT lock.

When wound up to max, you can still turn an e-Diff but you would require a force of approx 30,000nm!!

M

Semantics. 30000 Nm (Capital N thankyou as it is named after Sir Isaac, plus there should be a space between the number and the unit) would unlock (AKA break) most selectable and auto lockers. (And where have you obtained this magic number?)

If you look at a cutaway of the e-diff, it clearly contains carbon fibre clutch packs, similar to rally cars with hydraulic diffs. It can seemingly vary from open to (effectively) fully locked.

Originally Posted by isuzurover

(And where have you obtained this magic number?)

Have you forgotten where I work???

M

The clutch for a manual gearbox doesn't lock either, nor do the hydraulic clutches in automatic gearboxes but by design they all effectively do.

Originally Posted by Graeme

Is the e-diff ready differential a normal e-diff with some parts missing, implying that the e-diff is stronger than the standard open diff?

The e-diff ready, is less the stepper motor. The locker and non locker are slightly different, different bearings are used, so internally they are not totally identical. As far as a particular strength of one or the other, I am not rendering an opinion.

The idea being providing a e-diff kit, with the extra bits such as wiring, ecu, stepper motor, so you can convert to a locker after that. I agree as to the responses on the description of the clutch plates. You have to have give in the system or things would / could break, and still do on occasion.

I have an interesting scenario to ponder regarding my E diff. The other day I noticed a small occasional clunk when turning corners and didnt think much more of it. On the weekend I went for a drive to Werris Creek and near Dunedoo i got a reduced traction warning after coming through some water on corrugated dirt which I couldnt clear. When I got to Werris creek and turned around the clunking noise had got lots more serious and I figured that either the centre diff or the rear one was locked.
I drove home in the wet and figured out in the carpark at Phesents nest that part of my problem was the wires hanging down from underneath the back axle.

This afternoon I did some surgery and re spliced the wires back together. The cause of them getting broken was the flat plastic tags that hold the wires off the diff housing had broken and I suspect that they got entangled in the CV or axle. After I repaired the wires the reduced traction warning was still on and on investigation there was a stress fracture in the red wire where it goes into the plug that attaches to the diff. Repaired this and the reduced traction warning dissappeared.

When I backed the car out of the shed the diff still appeared to be locked but after a couple of circuits in the high school car park it seems to be behaving itself. Tomorrow will tell further I guess. I have the truck booked in for a service next week so I'll get them to test the actuator if they can.

So My questions are:
Is the plug that attaches to the bottom passenger side of the diff housing the temperature sensor?
If the temperature sensor went open circuit would the vehicle try and lock the diff as a failsafe?
Or is my wiring issue coincedental with a faulty actuator or other problem with the diff?

Regards,
Tote.