Front and Rear lockers - Need clarification - Help!

Cheshire

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My old Defender 90 had diff lockers that sent 50% of power to the front and 50% to the back. Problem was that if one front and one rear tire are slipping, it was stuck. My Wrangler Rubicon diff lockers sent 25% of power to each wheel, so it rarely got stuck.

Enter the Bronco
The Black Diamond has rear diff lock. What does this mean?? Do each rear tire have 50% of the power with no power in front? Is half the power sent rearward like the old Defenders?

The Badlands and Sasquatch package both have front and rear diff lock. Is this like the old defender with 50% power forward and 50% rear? If so, this is not nearly as good as the Rubicon's sending 25% of power to each wheel. I'm confused as to what exactly Ford is offering. Can anyone explain this to me?? Thanks!





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"Lockers" in the sense that Jeeps and Broncos use means that the left wheel turns along with the right wheel. So in the case of a rear locker, both rear wheels will spin no matter if one or both of those wheels have traction or not. The front wheels, in this example, would spin independently until one looses traction - whereas then the one front wheel without traction would spin freely while the other wheel would more than like just sit there because all of the power would be going to the front wheel that's spinning. The rear wheels would, however, help push the vehicle forward in a case where you lost traction in one of those front wheels.
Clear as mud? lol
 

Studawg

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All that's required to send 50% to the front and 50% to the rear is a center diff locker, in the transfer case.

For example, all 80 Series Land Cruisers came with a center diff lock standard. That is automatically engaged when going from 4Hi to 4Low.

A small fraction of the FZJ80 Series (1993-1997) came with additional electric lockers in the front and rear differentials. Thats how you get exactly 25% to each wheel.

If your D90 had one tire spinning on an axle, it wasn't locked. But Im pretty sure your D90 had 3 lockers as well.

As far as I can tell, Ford is offering conventional lockers that perform just like this.
 

BuckeyeinNV

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It sounds like your old Defender had a center differential lock. The Sasquatch package and Badlands are the same as a Wrangler Rubicon with front and rear locking differentials.

I was going to type out an explanation of how differentials work but the video below does a better job. Locking diffs are explained about halfway through the video.

Anytime you activate 4WD in a part time 4WD vehicle, the center is effectively locked. This is traditionally done with a transfer case but can be done with a differential. I assume your Defender was full time 4WD/AWD which is why it had a locking center diff button/level/whatever.

I assume the Bronco has a transfer case unless you opt for the "Advanced 4WD" or whatever they call it, but I haven't investigated that closely.

Anyway, locking the center only or putting it into 4WD without locking the front or rear basically means power is sent to front and rear equally but the wheels are still allowed to spin at different speeds, so if one wheel in front and one wheel in back lose traction, you're stuck.

If you then lock the rear diff, both front and rear get equal power, but the rear wheels are "locked" together and spin at the same rate even if one loses traction. So to get stuck, one wheel in front must lose traction, and BOTH wheels in the rear must lose traction.

If you lock both the front and rear, half the power is sent to front and back, and each set of wheels is locked together and spin at the same rate. So to get stuck, all 4 wheels must lose traction at the same time.

(I know this is a bit oversimplified if anyone is looking to rip it apart, lol)

So if you didn't understand all that, to just remember this:

From a traction perspective Front+Rear lockers>Rear locker>Center locker>center open diff>2wd

Go it? Good.

 
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Cheshire

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All that's required to send 50% to the front and 50% to the rear is a center diff locker, in the transfer case.

For example, all 80 Series Land Cruisers came with a center diff lock standard. That is automatically engaged when going from 4Hi to 4Low.

A small fraction of the FZJ80 Series (1993-1997) came with additional electric lockers in the front and rear differentials. Thats how you get exactly 25% to each wheel.

If your D90 had one tire spinning on an axle, it wasn't locked. But Im pretty sure your D90 had 3 lockers as well.

As far as I can tell, Ford is offering conventional lockers that perform just like this.
What you are saying isn't correct. When the D90 center locking differential ss engaged it sends 50% of the power to the front and rear axle each. If one wheel loses contact with the ground in the rear (for example) that wheel takes all the torque from the other rear wheel and it simply spins. Same with the front axle. This happened to me on many occasions, I would get stuck on ice and have one wheel spinning in the back and one spinning in the front and I was stuck. Without the diff lock on, it operated like simple AWD, if any wheel lost friction it didn't move.
 
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Cheshire

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It sounds like your old Defender had a center differential lock. The Sasquatch package and Badlands are the same as a Wrangler Rubicon with front and rear locking differentials.

I was going to type out an explanation of how differentials work but the video below does a better job. Locking diffs are explained about halfway through the video.

Anytime you activate 4WD in a part time 4WD vehicle, the center is effectively locked. This is traditionally done with a transfer case but can be done with a differential. I assume your Defender was full time 4WD/AWD which is why it had a locking center diff button/level/whatever.

I assume the Bronco has a transfer case unless you opt for the "Advanced 4WD" or whatever they call it, but I haven't investigated that closely.

Anyway, locking the center only or putting it into 4WD without locking the front or rear basically means power is sent to front and rear equally but the wheels are still allowed to spin at different speeds, so if one wheel in front and one wheel in back lose traction, you're stuck.

If you then lock the rear diff, both front and rear get equal power, but the rear wheels are "locked" together and spin at the same rate even if one loses traction. So to get stuck, one wheel in front must lose traction, and BOTH wheels in the rear must lose traction.

If you lock both the front and rear, half the power is sent to front and back, and each set of wheels is locked together and spin at the same rate. So to get stuck, all 4 wheels must lose traction at the same time.

(I know this is a bit oversimplified if anyone is looking to rip it apart, lol)

So if you didn't understand all that, to just remember this:

From a traction perspective Front+Rear lockers>Rear locker>Center locker>center open diff>2wd

Go it? Good.

Concerning the new Bronco,
If what you said is true, that by locking the rear diff, the front and rear get equal power and that power is shared equally by the two rear wheels, that would be great. I feel this capability in the Black Diamond would be enough for my off road aspirations.

I am curious what is going on when the rear differential is not locked. Will one slipping wheel cause the Bronco to get stuck or is there always equal power to the front and rear in 4WD?
 

BuckeyeinNV

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Concerning the new Bronco,
If what you said is true, that by locking the rear diff, the front and rear get equal power and that power is shared equally by the two rear wheels, that would be great. I feel this capability in the Black Diamond would be enough for my off road aspirations.

I am curious what is going on when the rear differential is not locked. Will one slipping wheel cause the Bronco to get stuck or is there always equal power to the front and rear in 4WD?
Whenever you're in four wheel drive in the Bronco (either 4H or 4L) the center is locked so 50/50 power front and rear. It would be the same as your Defender with center diff locker activated. So to get stuck, you'd have to lose traction in one wheel in front and one wheel in back.

Locking the other diffs is additive, so if you are in 4L and lock the rear the center and rear are locked, then if you lock the front the center, rear, and front are all locked.
 

Studawg

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What you are saying isn't correct. When the D90 center locking differential ss engaged it sends 50% of the power to the front and rear axle each. If one wheel loses contact with the ground in the rear (for example) that wheel takes all the torque from the other rear wheel and it simply spins. Same with the front axle. This happened to me on many occasions, I would get stuck on ice and have one wheel spinning in the back and one spinning in the front and I was stuck. Without the diff lock on, it operated like simple AWD, if any wheel lost friction it didn't move.
Nothing I said was incorrect. I’m fully aware of how lockers work. I said “I’m pretty sure the D90” was triple locked but I guess it only had the center diff lock. I don’t know what you are confused about.
 

MaverickMan

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Somebody throw the 4A transfercase option in this convo to really cross em up. :ROFLMAO:
My eagle has viscous coupler transfer case that one acts like a rubbery center limited slip. You start to get stuck then stop moving and no wheels spin, then you floor it and it starts spinning wheels again maybe one with traction if your lucky.
 

Zero_chance

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My old Defender 90 had diff lockers that sent 50% of power to the front and 50% to the back. Problem was that if one front and one rear tire are slipping, it was stuck. My Wrangler Rubicon diff lockers sent 25% of power to each wheel, so it rarely got stuck.

Enter the Bronco
The Black Diamond has rear diff lock. What does this mean?? Do each rear tire have 50% of the power with no power in front? Is half the power sent rearward like the old Defenders?

The Badlands and Sasquatch package both have front and rear diff lock. Is this like the old defender with 50% power forward and 50% rear? If so, this is not nearly as good as the Rubicon's sending 25% of power to each wheel. I'm confused as to what exactly Ford is offering. Can anyone explain this to me?? Thanks!
You’re referencing transfer case ability. Lockers simply lock the left and rear wheel together so they’re turning the same speed regardless of each sides traction surface/
 

Natai

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You’re referencing transfer case ability. Lockers simply lock the left and rear wheel together so they’re turning the same speed regardless of each sides traction surface/
And as I understand it, engaging the Bronco's 4WD effectively locks the transfer case to 50/50 between front and back. So if you also engage both lockers you're getting the 25% per wheel the OP mentioned.
 

Zero_chance

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And as I understand it, engaging the Bronco's 4WD effectively locks the transfer case to 50/50 between front and back. So if you also engage both lockers you're getting the 25% per wheel the OP mentioned.
Doing too much division. When a center section is locked whatever power is transferred from the t-case is available fully at both wheels as they are essentially one solid unit. Hypothetical situation, you’re stunting and get your bronco up on two wheels let’s say LF and LR wheels only on the ground, other two wheels in the air, the wheels on the ground will be transmitting all of the power available to it from the t-case in a front and rear locked situation, not half of what the t-case sent. There’s nothing in a solid locked axle that would try and divide the power aside from normal driveline loss. Axles aren’t smart enough to do division.
 

Natai

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Doing too much division. When a center section is locked whatever power is transferred from the t-case is available fully at both wheels as they are essentially one solid unit. Hypothetical situation, you’re stunting and get your bronco up on two wheels let’s say LF and LR wheels only on the ground, other two wheels in the air, the wheels on the ground will be transmitting all of the power available to it from the t-case in a front and rear locked situation, not half of what the t-case sent. There’s nothing in a solid locked axle that would try and divide the power aside from normal driveline loss. Axles aren’t smart enough to do division.
I stand corrected. I should have said it provides equal power to both wheels on the axle.
 

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