37s vs 40s: Is there really a need for 40s?

From what I can gather, you'll always be limited by the ball joints.

There are aftermarket BJs that claim to provide better strength over stock Dana 44 BJs, but any improvements will be marginal because the size is limited by the knuckles.

Like you can run 37s on D44s, but you have to either not wheel it hard enough to take advantage of the 37s, or get comfortable changing balljoints.

I was wondering specifically about "true" Dana 44 front axle going back to the 70s, rather than the hybrid Dana 44 center with Dana 30 knuckles that they gave the Wrangler.
 
From what I can gather, you'll always be limited by the ball joints.

There are aftermarket BJs that claim to provide better strength over stock Dana 44 BJs, but any improvements will be marginal because the size is limited by the knuckles.

Like you can run 37s on D44s, but you have to either not wheel it hard enough to take advantage of the 37s, or get comfortable changing balljoints.

Stretching the inner C yokes is the real issue. A stronger ball joint will not address that.
 
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Stretching the inner C yokes is the real issue. A stronger ball joint will not address that.

First I've heard of this. I've personally seen ball joints fail, I've not seen an inner C bend. Does that happen a lot?
 
So does the thicker C's offered by the after market (currie, dynatrak, ECGS, etc...) negate this issue of the holes "stretching" or is the bearing stress still high enough to cause issues? Or is the issue from the actual install of the ball joint stretching the hole?
 
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So does the thicker C's offered by the after market (currie, dynatrak, ECGS, etc...) negate this issue of the holes "stretching" or is the bearing stress still high enough to cause issues? Or is the issue from the actual install of the ball joint stretching the hole?

Best way to solve the problem.
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I was wondering specifically about "true" Dana 44 front axle going back to the 70s, rather than the hybrid Dana 44 center with Dana 30 knuckles that they gave the Wrangler.

The benefit of the old Fords is the ball joints press into the knuckles and not the C's. Ball joints could be a bit bigger but not sure.

For reference Ford HP 44
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I'm wondering the same thing. I'm planning on going to 37s, just not sure the axle yet.

It looks like JK Rubicon axles are probably enough, but maybe not. ECGS 489s are a little bit better, but at that price you're almost at custom 60s when going to 65 WMS.

My build uses JK Rubicon axles, 37's on 17x9 with 4.75" of backspacing. Front clears fine with JK axle allowable 6" of steering throw. Slight tire rub on right side LCA when at full droop and I'm running 14" coilovers limited to 12.5"-13" of travel. The rear, however, the top of the tire rubbed the out-boarded coilover. Will at ECGS is building me a 65 WMS 489, 35 spline and a 65 WMS 40-spline Dana 60. Message me if you want further specifics.
 
The Currie HD60 states that it utilizes factory knuckles (JK). Does anyone know what ball joints it uses? Does it maintain the JK Dana 44 ball joints?

I was previously set on staying at the 35" tire size and going with a HP44 to maintain clearance. I was just about to pull the trigger on a Currie HP44, but I recently came to the conclusion that I will ultimately go to at least 37s so that I can get into a sticky. So, I might as well invest in an axle that will hold up to the larger tires on the front end. So I am now looking and comparing HP60s which will get me the beefier ball joints as well as 35 spline and larger R&P to better withstand the sticky. Anyone know of one for sale in the 65"(+/-) wms range let me know.
 
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The Currie HD60 states that it utilizes factory knuckles (JK). Does anyone know what ball joints it uses? Does it maintain the JK Dana 44 ball joints?
If it didn't, they would make a big point of it, that and the ball joints have to work with the knuckles. Unless they managed to make a hybrid version, that means they will be JK size. There is zero reason to build that axle. The HP 44 JK front center they have will work quite nicely with the "1 ton" outers. There is zero logic to reverse that.
I was previously set on staying at the 35" tire size and going with a HP44 to maintain clearance. I was just about to pull the trigger on a Currie HP44, but I recently came to the conclusion that I will ultimately go to at least 37s so that I can get into a sticky. So, I might as well invest in an axle that will hold up to the larger tires on the front end. So I am now looking and comparing HP60s which will get me the beefier ball joints as well as 35 spline and larger R&P to better withstand the sticky. Anyone know of one for sale in the 65"(+/-) wms range let me know.
The weak point isn't the HP gear set.
 
My build uses JK Rubicon axles, 37's on 17x9 with 4.75" of backspacing. Front clears fine with JK axle allowable 6" of steering throw. Slight tire rub on right side LCA when at full droop and I'm running 14" coilovers limited to 12.5"-13" of travel. The rear, however, the top of the tire rubbed the out-boarded coilover. Will at ECGS is building me a 65 WMS 489, 35 spline and a 65 WMS 40-spline Dana 60. Message me if you want further specifics.

Whoa 40spline!? What pushed you to the 60 rear vs 489s with 35s front/rear? Were they pretty close in price?
 
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Whoa 40spline!? What pushed you to the 60 rear vs 489s with 35s front/rear? Were they pretty close in price?

The axle isn't available to the public, yet. Low pinion, high clearance Dana 60, 40-spline with JK backing plates.. I'm told it only loses 3/8" of ground clearance at the center section over their 489. Since it's not out yet, I got a pretty good deal on the pair of axles.
 
Just bolted one of the new ecgs in a JKU. The new housing and tubes are very impressive,.picture doesn't do the dia of the tubes justice.

img_1_1705026730092~2.webp
 
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