Front Axle Disconnect?

usmcss

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Just to try and understand this a little better.

When the vehicle is in 2WD, the front Axle is disconnected and the rear is connected. What then is the rear locker for? Is it only one rear wheel that is locked during 2WD and the rear locker button will lock both wheels so they have even torque?

Is the Locker System similar to Hub Locks except the Locker system locks and unlocks the Axle Instead of locking and unlocking the Wheels?

Thanks guys!!!
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AZCrawl

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Just to try and understand this a little better.

When the vehicle is in 2WD, the front Axle is disconnected and the rear is connected. What then is the rear locker for? Is it only one rear wheel that is locked during 2WD and the rear locker button will lock both wheels so they have even torque?

Is the Locker System similar to Hub Locks except the Locker system locks and unlocks the Axle Instead of locking and unlocking the Wheels?

Thanks guys!!!
This system is only activated when you are in 2H. It is intended to save fuel, because your front drive shaft and axles are disconnected and not turning as you drive down the road.

The front and rear lockers are a totally different thing. These are only able to be activated in 4L. It locks the axles, so both wheels on each axle that is locked turn and help push the Jeep forward on difficult terrain.
 

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usmcss

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This system is only activated when you are in 2H. It is intended to save fuel, because your front drive shaft and axles are disconnected and not turning as you drive down the road.

The front and rear lockers are a totally different thing. These are only able to be activated in 4L. It locks the axles, so both wheels on each axle that is locked turn and help push the Jeep forward on difficult terrain.
Thanks a lot Azcraw!!!
 

ThrillerR1

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If anyone is curious about what it looks like inside:

Nice info! So this gives me an idea. Put in an overrride switch so that the FAD can select 2 wheel drive low range. :rock:

Might not be as useful as I'm thinking but I like the idea of having the option.
 

usmcss

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So in the video and on my Rubicon I only see one of these FAD Boxes on the passenger side. So it only disconnects the passenger side and not the front driver side?
 

Beowulf

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I bet RCV makes two versions. One solid single piece axle and one 2 piece replacement.
 

usmcss

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So is it both front wheels that are disconnected or just the passenger side? If its both, is the other side disconnected in the front differential?
 
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So is it both front wheels that are disconnected or just the passenger side? If its both, is the other side disconnected in the front differential?
Only the passenger side axle is disconnected. The passenger side axle is actually two pieces instead of one piece like the driver side axle. When disconnected in 2H, the passenger side tire and half of the axle spins free. The driver side tire spins the driver side axle which is connected to the differential. The internal gears of the differential rotate the other half of the passenger axle (in opposite direction). The pinion and ring gear remain static along with the front driveshaft. I believe that is how it works.
 
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Jeepsterfreak

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Nice info! So this gives me an idea. Put in an overrride switch so that the FAD can select 2 wheel drive low range. :rock:

Might not be as useful as I'm thinking but I like the idea of having the option.

Wait. you are saying to override the system by keeping the FAD on (disconnected) while in 4L to create a 2L? Not sure that would work because you are now turning the front ring/pinion which will be sending power only to the driver side wheel because the passenger side is disconnected. Or maybe it would work because the diff would just spin without sending power to the driver wheel. :facepalm:

Someone smarter than me would have to explain.
 
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brantb

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Wait. you are saying to override the system by keeping the FAD on (disconnected) while in 4L to create a 2L? Not sure that would work because you are now turning the front ring/pinion which will be sending power only to the driver side wheel because the passenger side is disconnected. Or maybe it would work because the diff would just spin without sending power to the driver wheel. :facepalm:

Someone smarter than me would have to explain.
I would work as long as you only had the real locker on. If you activated the front you would be in 3 wheel drive
 
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usmcss

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Only the passenger side axle is disconnected. The passenger side axle is actually two pieces instead of one piece like the driver side axle. When disconnected in 2H, the passenger side tire and half of the axle spins free. The driver side tire spins the driver side axle which is connected to the differential. The internal gears of the differential rotate the other half of the passenger axle (in opposite direction). The pinion and ring gear remain static along with the front driveshaft. I believe that is how it works.
Awesome!!! Thank you buddy!!! Makes sense now!!!
 

usmcss

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It appears that although the Axle Disconnect is on the passenger side it also disconnects the driver wheel from the Drive. Not sure how the whole Axle is disconnected from that video above that shows the CAD teardown.
 
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Jeepsterfreak

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It appears that although the Axle Disconnect is on the passenger side it also disconnects the driver wheel from the Drive. Not sure how the whole Axle is disconnected from that video above that shows the CAD teardown.
The driver side is not disconnected, only the passenger side. The front differential is the reason why the ring/pinion gears and front driveshaft don’t rotate. The internal diff gears are spinning instead of the ring/pinion which is the reason the front driveshaft doesn’t spin in 2H. The internal diff gears do rotate the inner half of the passenger axle but it is disconnected from the outer half of passenger axle because the collar shown in the video is offset and not locking the passenger axle halves together. On the TJ and JK everything rotates because it does not have a FAD. The YJ was last wrangler to use FAD.

So why did Jeep return to FAD? Maybe to increase mpg slightly. It puts less wear and tear on the ring/pinion and front drive shaft and their associated bearings and seals. Puts more wear and tear on internal diff gears.

Attached is an illustration on YJ front axle. JL works same way but uses an electric motor instead of vacuum to move the collar. You can see parts 2 & 3 makes up the passenger axle. The collar locks these two parts together. Part 1 is the driver side axle which is one piece.

You could essentially add a FAD to your JK by installing locking front hubs. In theory you would only need one side unlocked to replicate Jeeps FAD design.

This system is used in RAM trucks.

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