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Diff locks.

DaveB

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Thats an interesting question? I wanted to say you will still have drive to the front, but without a lock on the diff, the wheel with resistance will likely not get drive as the power will go to the side with no resistance. However now I think about it, with no half shaft I am second guessing myself and I can’t picture what is happening inside the diff without a half shaft?
If the centre diff is locked and the rear diff is locked you will have 50% drive to front axle and 50% to rear axle.
As the rear is locked they will get 50:50 or 25% each
The front will share 50% but the split will change depending on which wheel has least grip.
So if one of the front wheels has zero grip it will be getting 50% of the total vehicle drive for no return.
 
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255/85

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And the spider/side gears in the front diff will be spinning madly and probably fry in a few miles. I'd lock the front (or whichever diff has the broken shaft) if it would at that point.

On pavement you'd leave it locked but unlock the transfer case and other diff..I think.
 
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AnD3rew

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If the centre diff is locked and the rear diff is locked you will have 50% drive to front axle and 50% to rear axle.
As the rear is locked they will get 50:50 or 25% each
The front will share 50% but the split will change depending on which wheel has least grip.
So if one of the front wheels has zero grip it will be getting 50% of the total vehicle drive for no return.
Yes that was my initial presumption, I think that’s right
 

Solmanic

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I finally had a chance to fully test the offroad buttons...

Centre diff lock - OK.
Rear diff lock - no engagement. Only the dreaded flashing "I'm trying to engage" light.
Front diff lock - cannot test until the rear successfully engages - pressing the button gives the proper "conditions not met" alert.

I put it in offroad mode so I could see the status of all three diffs. The centre showed locked, but the rear would just churn and not engage. Unlocking the centre diff then doing a few turns would successfully clear the flashing rear diff warning. I tried driving straight, turning, forwards & backwards but no luck. Surface was loose gravel.

In the past I've had a similar failure to engage one of the cross axle Eaton E-lockers in my G-Wagen and it was found to be a sticky solenoid. Maybe a hit with a hammer? But I'll leave that kind of surgery to the dealer. At this stage I'm putting it down to just first operation mechanical stiffness but I would have thought the dealer should have gone through and engaged & disengaged everything in the PDI.
 

Solmanic

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I finally had a chance to fully test the offroad buttons...

Centre diff lock - OK.
Rear diff lock - no engagement. Only the dreaded flashing "I'm trying to engage" light.
Front diff lock - cannot test until the rear successfully engages - pressing the button gives the proper "conditions not met" alert.

I put it in offroad mode so I could see the status of all three diffs. The centre showed locked, but the rear would just churn and not engage. Unlocking the centre diff then doing a few turns would successfully clear the flashing rear diff warning. I tried driving straight, turning, forwards & backwards but no luck. Surface was loose gravel.

In the past I've had a similar failure to engage one of the cross axle Eaton E-lockers in my G-Wagen and it was found to be a sticky solenoid. Maybe a hit with a hammer? But I'll leave that kind of surgery to the dealer. At this stage I'm putting it down to just first operation mechanical stiffness but I would have thought the dealer should have gone through and engaged & disengaged everything in the PDI.
Scrap all that…
After a pause to type that then trying again, now all diff locks engage fine 🙄, but I cannot get the front & rear lockers to progressively disengage.

I can only get all three to disengage together by unlocking the centre diff. Go figure.
 

DaveB

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Scrap all that…
After a pause to type that then trying again, now all diff locks engage fine 🙄, but I cannot get the front & rear lockers to progressively disengage.

I can only get all three to disengage together by unlocking the centre diff. Go figure.
By unlocking in sequence do you mean front first, then rear then centre?
 
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DCPU

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I would have thought the dealer should have gone through and engaged & disengaged everything in the PDI.

According to the latest version of the PDI form I've seen (v1.1.5) they should have:
Screenshot_20230916_072859.jpg


My agent refused to give me a copy of the completed form, dispite the fact I'd paid £200 for it.
 

rovie

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Scrap all that…
After a pause to type that then trying again, now all diff locks engage fine 🙄, but I cannot get the front & rear lockers to progressively disengage.

I can only get all three to disengage together by unlocking the centre diff. Go figure.
I had the same thing the first time. I then drove together with my dealer. At first, he couldn't do any better. We then drove a longer distance (maybe 30 metres or more) in a slight sideways motion. Then the locks came out one by one (first at the front, then at the back).
 

Solmanic

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By unlocking in sequence do you mean front first, then rear then centre?
Yes. When I press the buttons in reverse order I just get the flashing light on the button, but the corresponding light stays on solid on the warning panel and no indication on the off-road mode display on the center screen that either diff is trying to disengage. When I turn the wheel I can feel both diffs are still engaged but as soon as I stop and unlock the centre diff, everything unlocks almost immediately - but as mentioned in other posts I have to do a couple of sharp turns for the lights to go off.
 

Solmanic

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I had the same thing the first time. I then drove together with my dealer. At first, he couldn't do any better. We then drove a longer distance (maybe 30 metres or more) in a slight sideways motion. Then the locks came out one by one (first at the front, then at the back).
Ah, maybe I’m not driving far enough. I’m only going back and forth on my driveway about 15m.
 

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Ah, maybe I’m not driving far enough. I’m only going back and forth on my driveway about 15m.
Unlocking the centre diff to disengage all three and then re engaging the centre if needed is as easy as looking up and disconnecting the front and back diffs in my books 👍🏼
 

DaveB

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Unlocking the centre diff to disengage all three and then re engaging the centre if needed is as easy as looking up and disconnecting the front and back diffs in my books 👍🏼
I agree if you want all three out.
Unlocking the rear first unlocks the front automatically as well.
 
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From my experience
Firstly the vehicle is new then the centre lock is mechanical and the other 2 electric. The centre engages and disengages as per the leaver position the other two locks disengage as soon as there is zero current in the solenoid . It’s the indication /detection system that’s lagging behind as it uses wheel speed to determine disengagement. Then frantic pushing of buttons confuses us and it . I think practice makes perfect half an hour of buggerin around on a wet grass bank in low off road should do it.
 

DCPU

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It’s the indication /detection system that’s lagging behind as it uses wheel speed to determine disengagement.
I wonder if it could be configured the other way around with just some "simple" code ~ all lights go off at button push, and then wheel speed monitors for confirmation of disengagement, if it doesn't get it in a predetermined distance/time then the lights start flashing?
 

rovie

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Today I was out in my field and forest and used the reduction and the locks. I do that regularly. The track was very soggy from the rain. Both the reduction and the centre differential lock were easy to engage. The rear and front axle locks were also engaged immediately. I drove very slowly when engaging them. Switching them off one after the other also worked. However, I had to drive about 20 metres until the indicators went out. All in all, I am very satisfied with the functions.
 

Tinerfeño

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It would be impossible to build an electronics free vehicle these days. So I guess we just have to accept some.. The grenadier has way les than most other cars, doesn’t the new defender have 17 ecu’s?
I quickly browsed the New Defender EPC through and found easily 37 ECU's, most in the body functions. In addition practically all electrical components, switches, sensors, motors, etc. have a circuit board at least for communication purposes. When the model was introduced in Frankfurt Motor Show I tend to remember that they said in the very early stage "Defender has always been robust" and somewhere near the end "the car contains 82 computers". So that for the robustness :rolleyes:

I had hoped that IG would have been far more simple that it now appears. Why the basic body functions, at least lights, wipers and washers, possibly also heater, couldn't have been made with old-school switches and relays that you can easily override to get the things working if someting fails?

I really like the chassis, axles and suspension of IG but would have preferred a manual transmission. Now even the electronic gearstick may cause limp mode or in the worst case paralyse the entire car. And manual is better in off-road and towing. As automatic transmission is a constant force device every obstacle stops it if you are not able to react to that in advance. Manual is a constant speed device that is absolutely fantastic in off-road conditions.

My trusty Disco 1 is now 30 years old and has about 600000' kilometres. I may need to stick to that ...
 

Tinerfeño

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Rear diff lock is normally built stronger than the front in most 4X4 set ups. I thought for some reason the GREN had both front and rear diffs lock together with no option to have them independent, but I saw or read that wrong, I think. If it is Back 1st and Front 2nd than that makes sense and to be honest with Elocks it's a similar config to several other makers.
In my opinion they need to be equally strong.

I also undestand why rear is forced on before fron diff lock. Front diff lock (alone or with the rear) makes steering difficult as it causes heavy understeer. Those driving in competitions want to use it occasionally first but for normal use the configured system is OK.
 
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