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392 Dana 44 axles beefed up for 392?

sourdough

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With all the HP and torque increase have upgrades been made to the 392's axles ?
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Comac90

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With all the HP and torque increase have upgrades been made to the 392's axles ?
maybe someone can confirm, but as I understand it, the front axle is from the Mojave with the cast-iron knuckles and thicker tubes. Rear brakes are the larger brakes from the 4xe.
 

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I heard early talk of the Mojave housing which sounds like a good upgrade all Rubicons could use. I guess the JT Mojave rear axle width is the same as a JL's. 4xe brakes are news to me. Was anything done to axle shafts? Folks are twisting the splines on rear shafts and breaking joints.
From what I have been told and have also read the front axle tubes are thicker and the front and rear brakes are larger in diameter, why they didn't just go with the Jeep performance upgrade kit may be due to the 17" wheels. It is hard to get a straight answer from most dealers, they didn't even know about Jeep using the Gladiator grille on the 392 due to having a higher flow rate because there is more "open area" on a Gladiator grille than there is on a stock JL grill
Note that the 392 boasts enhanced whoa to match the added go, with larger vented (13.8 x 0.9-inch versus 13.4 x 0.6-inch solid units) rear rotors clamped by larger single-piston calipers (2.0- versus 1.9-inch diameter).
 

JeepinJason33

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Just the eyeball check from my neighbors next to mine and they look the exact same.
 

Comac90

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Just the eyeball check from my neighbors next to mine and they look the exact same.
Itā€™s the wall thickness thatā€™s different... 10mm vs 7.3mm or something close to that.
 

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JeepinJason33

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Itā€™s the wall thickness thatā€™s different... 10mm vs 7.3mm or something close to that.
I have not seen any documentation on that yet. Would almost have to cut one up unless Jeep releases that it is a different thickness and if it was, I think they would have advertised it.
 

Arterius2

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I have not seen any documentation on that yet. Would almost have to cut one up unless Jeep releases that it is a different thickness and if it was, I think they would have advertised it.
The likes of Jalopnik and almost every major publication has reported that itā€™s using the thicker ā€œMojaveā€ style axles.

My money is on that it is.
 

Comac90

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I have not seen any documentation on that yet. Would almost have to cut one up unless Jeep releases that it is a different thickness and if it was, I think they would have advertised it.
Google is your friend - Jalopnik, Four Wheeler, Motor Trend, and several others have all reported on it and Jeep talked about it at EJS.

Bottom line: The 392 uses the entire front axle from the Mojave including the larger brakes, thicker tubes, and cast-iron knuckles ... and the rear brakes are the larger ones from the 4xe.

T
 

BCMgunner

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Iā€™ve heard all the above.

I havea MetalCloak rear diff skid coming in this week. If it fits, rear tubes are same diameter as standard JLUR but still possibly thicker walls (but same diameter). If they donā€™t, the tubes are thicker in diameter.
 

Comac90

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Iā€™ve heard all the above.

I havea MetalCloak rear diff skid coming in this week. If it fits, rear tubes are same diameter as standard JLUR but still possibly thicker walls (but same diameter). If they donā€™t, the tubes are thicker in diameter.
Keep us posted. I watched (or read?) somewhere the OD is the same, just wall thickness increased. Iā€™ll see if I can re-find where I saw that...
 

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Comac90

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CV joints are a plus over stock u-joints. Any info on axle shaft diameters or splines front and rear.
same as the Rubicon 44, but FAB has been deleted. Someone on here said the front shaft on the FAB side was still collared, but that doesnā€™t make sense to me.

Whoā€™s gonna be first to throw in some RCVs and see if that stock shaft isnā€™t collared? šŸ˜‰
 

jessedacri

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same as the Rubicon 44, but FAB has been deleted. Someone on here said the front shaft on the FAB side was still collared, but that doesnā€™t make sense to me.

Whoā€™s gonna be first to throw in some RCVs and see if that stock shaft isnā€™t collared? šŸ˜‰

The FAD has been deleted but only symbolically, really. They just removed the electronic bit and put a cover plate instead - and its now a one piece axle shaft, but the weak cast FAD housing is still there in the axle assembly.
 

MARSHMELLA

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I want to play too.......

My babies mommaā€™s cousin said she heard someone at the grocery say that the 392 is beefed up in some places but not in other places. Basically they are kind of the same, but with some differences. šŸ¤Ŗ
 
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Comac90

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The FAD has been deleted but only symbolically, really. They just removed the electronic bit and put a cover plate instead - and its now a one piece axle shaft, but the weak cast FAD housing is still there in the axle assembly.
thanks for the clarification. Thatā€™s kinda what I meant ... although I wouldnā€™t use the word ā€˜symbolicallyā€™. the 392 does not have the FAD system at all - it is deleted. But, to your point, the hole in the housing is still there. Not sure itā€™s weak, though. Weaker than a full tube? I would think .. relative. Iā€™d certainly rather it be a solid tube.

That said, I havenā€™t researched failures of the housing at the FAD opening. Maybe thatā€™s an issue Iā€™m unaware of???

great to know it is actually a one piece axle and not collared. That was one of the big questions Iā€™d wondered since it was brought up earlier.
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