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.........Why isn't just "Locked" good enough, why do you have say rigidily locked?

......Nowhere in that write up do they say both differentials are locked together.

........Also, nowhere in that write up do they say it "rigidly locks"....

What Transfer Case does you Ford F150 have? Not all transfer cases work the same....
Most Transfer cases that are capable of Full Time 4WD, have a differential, with additional equipment to lock that differential if its capable of Part Time 4WD....
Mongo, you must be or have been an English grammar teacher. lol
Locked, ridgid, ridgidly locked...whats the big deal.
By the way you didn't pick up on my incorrect spelling of ridgid which should be rigid!
RIDGID is the brand name of a tool line Home Depot sells.

My F150 does not have the Tcase with the 4Hi AUTO feature. Its strictly a part time 4Hi or 4Low only Tcase.
In 4Low a motor engages low ratio gears in the Tcase to increase engine torque and transfer that torque to the front diff.
Ford F150 4x4 trucks also use whats called an IWE (Integrated Wheel End) at each front wheel hub which decouples the wheels from the front axles during 2Hi mode. This is accomplished by the use of a vacuum operated mechanical clutch at each wheel hub similar to the hand operated wheel lockers on old school 4x4's.

My XJ's NP242 Tcase is has 2Hi, 4Hi part time, 4Hi full time and 4Low options.
In 4Hi full time mode, a clutch pack in the Tcase allows front to rear diff slippage when turning.
Not so when in 4Low or 4Hi part time.

Back to GC's eLSD.
My point is when in 4Low and say doing some serious rock crawling wheeling its beneficial to have both rear wheels rigidly locked (haha) instead of an electrically operated clutch which engages/disengages on the fly.
For example, when going up a steep rocky/bolder incline with one rear wheel off the ground, you want that wheel to have full torque applied the moment it finally touches down.
There's a reason hard core rock crawlers install rear diff lockers instead of relying on a LSD diff.

The clutch pack in the eLSD far as i can tell could be firmly engaged 100% of the time only when in 4Low.
It likely wouldn't be as good as a true locker with probably some clutch slippage.
But the GC is not a Wrangler Rubicon and Jim_in_PA is probably right in that the eLSD operates the same whether its in 4Low or 4Hi.

Again from the Owner's Manual:
....When additional traction is required, the 4WD LOW
position can be used to lock the front and rear driveshafts
together and force the front and rear wheels to rotate at the
same speed....

Note the word 'lock'. Is the Owner's Manual also misleading?
Whether 'lock' should be taken as face value the true meaning of the word or whether they really mean rigidly coupled.
I don't know how my GC's Tcase transfers torque to the front diff in 4Low the reason i'm interested in all this.
Mongo, i'll take your explanation that it uses the clutch in all modes of operation which does make sense.
 

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Rigidly locked vs locked is an aside point....
It's just confusing when you change the terms...
And, like I pointed out the O.M. says Locked, not Rigidly Locked, so pointing to the O.M. saying its locked doesn't mean you're right....

The point is claiming the Transfer Cases Locks the differentials together is confusing... ....very confusing to folks that don't understand how Transfer Cases and Differentials work.... ....at one point you said the Transfer Case locks both differentials, sure its probably a typo, you missed a word, but you see how confused the point becomes.....

The NP242 works very differently than the MP3023 and Ford F-150 Transfer Cases sounds like the NP231 in the Wranglers..... ...yet they all some things in common....

The MP3023 has only one motor, and all the photos and things I've read about it, the shift fork for the planetary gearset is connected to the linkage to apply pressure to the Clutch Pack. So, as the motor rotates, it increases the pressure on the clutch pack till it rotates to the extreme which applies the most pressure on the Clutch Pack and moves the shift fork to engage the planetary gearset to shift into 4LOW, which has to apply full pressure on the clutch pack to get there, i.e. locks the front/rear driveshafts to the same speed...

I see plenty of evidence the eLSD locks, does it stay locked constantly while in 4LOW, I don't know... ...but when needed, it locks, including in Automatic 4WD...

Now out of curiosity, I have never owned a vehicle with decoupling front wheels? Why do they decouple? Is the drag from the front drivetrain that great? Do they have a locked differential in the front, that is why you need to decouple if you want to drive on-road?
 

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Rigidly locked vs locked is an aside point....
It's just confusing when you change the terms...
And, like I pointed out the O.M. says Locked, not Rigidly Locked, so pointing to the O.M. saying its locked doesn't mean you're right....



Now out of curiosity, I have never owned a vehicle with decoupling front wheels? Why do they decouple? Is the drag from the front drivetrain that great? Do they have a locked differential in the front, that is why you need to decouple if you want to drive on-road?
Rigidly locked vs locked is an aside point....
It's just confusing when you change the terms...
And, like I pointed out the O.M. says Locked, not Rigidly Locked, so pointing to the O.M. saying its locked doesn't mean you're right....
I see you're still hung up on the work ridgid or is it rigid.
Look, my '18 Trailhawk's Owner's manual uses the word LOCK when describing 4Low and the procedure to enable it.
If the word LOCK is good enough for my official Jeep Owner's manual, thats good enough for me.
I think i already get your point about using the word ridged or is it rigid.
Rigid and lock can be construed as somewhat redundant word meanings.

As you say (by the way i respect your technical knowledge regarding these GC's as i'm a newcomer to these GC's)...... ....is the front differential not rigidly coupled or locked with the front diff when applicable say AUTO mode?
Otherwise there would be an appreciable amount of Tcase clutch slippage to render front wheel traction a waste of time.
I'd think that the Tcase front diff clutch is enabled as fully as possible to rigidly lock the front diff.

I see plenty of evidence the eLSD locks, does it stay locked constantly while in 4LOW, I don't know... ...but when needed, it locks, including in Automatic 4WD
Thank you, thats the primary thing i was questioning about in 4Low mode.
Don't really care about AUTO 4Hi mode, the eLSD is what it is in those modes and my guess at this point also in 4Low.
 

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I see you're still hung up on the work ridgid or is it rigid.
Look, my '18 Trailhawk's Owner's manual uses the word LOCK when describing 4Low and the procedure to enable it.

If the word LOCK is good enough for my official Jeep Owner's manual, thats good enough for me.
I think i already get your point about using the word ridged or is it rigid.
Rigid and lock can be construed as somewhat redundant word meanings.
rigid
[ rij-id ]
adjective
  1. stiff or unyielding; not pliant or flexible; hard:a rigid strip of metal.
  2. firmly fixed or set.
  3. inflexible, strict, or severe:a rigid disciplinarian; rigid rules of social behavior.
  4. exacting; thorough; rigorous:a rigid examination.
  5. so as to meet precise standards; stringent:lenses ground to rigid specifications.
  6. Mechanics. of, relating to, or noting a body in which the distance between any pair of points remains fixed under all forces; having infinite values for its shear modulus, bulk modulus, and Young's modulus.
"Ridgid" can not be found in the dictionary....

I've said from the beginning, its a minor point, adding the word rigidly locked to lock if anything is giving it a new meaning that isn't true.

As you say (by the way i respect your technical knowledge regarding these GC's as i'm a newcomer to these GC's)...... ....is the front differential not rigidly coupled or locked with the front diff when applicable say AUTO mode?
Um, wow, I guess in a way the the front diff is a rigid structure, but its locked to itself?
But this has been repeated ad nauseam, all front diffs on all WK2's are open diffs, none of them have a locking diff, the diff never locks....
So let me say it one more time, the front diff on all WK2's is an open Diff, it has no equipment to lock or limit slip except for the brake traction feature.....

Otherwise there would be an appreciable amount of Tcase clutch slippage to render front wheel traction a waste of time.
I'd think that the Tcase front diff clutch is enabled as fully as possible to rigidly lock the front diff.
How do standard transmission vehicles with dry clutches ever get around? If a slipping clutch renders traction to the wheels at end of the drivetrain a waste of time, how did any of these vehicles ever get moving from a stop, where you have to slip the clutch a lot?

Um, you understand the Front Differential and the Transfer Case are totally separate units?

The wet clutch pack in the MP3023 in the WK2 (since the WK2 doesn't use all the features on the MP3023 and expands on the features it does use) will slip as needed in Automatic4WD mode (the default) mode. In the 4LOW mode it locks....

Remember, if you're driving straight down the road, all 4 wheels are turning at the same speed, its only when you turn or a wheel slips do they turn at different speeds.... ....so in Automatic4WD mode, with the clutch at partial pressure, it only slips when turning or a wheel slips... ...and how much pressure is on the clutch pack will determine how much torque it will take for it to start slipping and how much of a torque split there will be while it slips..... ...there is no torque split if it is not slipping...

The front and rear driveshafts attach to the transfer case, the differentials are totally separate, in the axle pumpkins, they are not in the Transfer case, if they were, then you would need 4 driveshafts, one per wheel.... ...I don't know why you keep insisting the Transfer Case is locking differentials, it doesn't....

At least at first, you said it locked the front and rear differentials together, which isn't true, but looking at a certain perspective that most people would not even imagine, it could lock the inputs to the diffs together. That is just really confusing, and will confuse people that don't understand drivetrains... ....now you've insisted several times the transfer case is locking the differentials, it just does NOT, not in anyway....

If the clutch pack in the Transfer Case locks, it locks the front and rear driveshafts together....
That does nothing to the differentials.... ....the left and right wheels can still turn at different speeds....
The eLSD will limit slip or lock, but there is only a rear eLSD, so only the rear wheels will limit slip or lock left/right....

Thank you, thats the primary thing i was questioning about in 4Low mode.
Don't really care about AUTO 4Hi mode, the eLSD is what it is in those modes and my guess at this point also in 4Low.
 

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Hey Mongo, i already knew and get it already that a clutch in the Tcase transfers torque to the front diff in AUTO (4Hi).
How else would these Jeeps transfer torque to the front diff on the fly.
I was only questioning if that was also true in 4Low.
And yes i know the front diff is open as in most if not all consumer 4x4 vehicles.

Far as ridged vs. rigid, just having some fun after you started to correct my usage of words.
Yeah I discovered during posting here i was spelling it wrong, thats all.
The Ridgid Tool Company and Home Depot should pay me a royalty for free advertising here. lol

I think you're taking all this way too serious.
 

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No, I'm getting a little frustrated... ...I didn't mean to sound angry... ....I'm pointing how the way your wording a lot of the concepts you're trying to get across can confuse folks....

I'm trying to point out what is confusing here.... you say shifting into 4LOW locks the differentials together, I can guess at what you mean, cause I know how it works, but many folks do not..... ...and they will think the WK2 has front and rear locking differentials that are controlled by the transfer case....
 

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Mongo,
first of all as i mentioned earlier, i respect your GC knowledge and experience of which i learned a lot in the past and others here too.
IMO no doubt about it, you are indeed a valuable asset to this forum.
Having said that, i'm going to end this particular discussion at least on my part because of your relentless knit pick'n BS before we get into an escalating pissing contest where one or both of us will regret.
That does not mean i hold any hard feelings towards you and will continue to add my 2 cents to any threads that you and i participate in.
Now lets both of us have a good day!
 

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I said I didn't mean it to sound angry, I'm not.... ....its not a pi$$ing contest....
 
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