Build a HP30, LP44 or Currie 44?

PNW_LJ

Crazy Russian
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Here's my plan:

'04 LJ non-Rubi (LP30 and 44 rear)
42RLE
Savvy Midarm
35s

What front axle would everyone recommend I go with?

I see 3 options:

HP30 w/5.13s
Rubi LP44 w/5.38s
Currie 44 w/5.38s

HP30 is obviously the cheapest/easiest swap. But this is my daily driver, so I think I would want all the gear I can get with my 42RLE.
I would love a Currie 44 for the 5.38s, HP, and increased strength, but dang that price stings.


I think it boils down to how big of a difference 5.38s would make over 5.13s in daily driving, and whether the increased strength of the Currie is worth it. Let me know what you guys think, any input is appreciated!
 
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Have you broken the current 30 yet? If not, then this becomes a question of gearing.
 
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Have you broken the current 30 yet? If not, then this becomes a question of gearing.

But I don't want to wait until it breaks. I go wheeling hundreds of miles from home, and being stranded with a broken CA bracket, or bent housing doesn't sound that appealing.

I understand that the weak point in the stock TJ axles is the shafts and outer components, but I guess the question is how often do people bend housings/Cs, and brackets on the stock axles?
 
..., but I guess the question is how often do people bend housings/Cs, and brackets on the stock axles?

I'll go out on a limb and say it is hardly a common occurrence. I would rather add Currie mini skids to the lower control arm brackets or add new brackets long before fixing that problem with an entirely new axle. Which puts this back to a gearing question.
 
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"how often do people bend housings/Cs, and brackets on the stock axles?"

Most of us "never". Weld on reinforcement if worried.
 
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I'll go out on a limb and say it is hardly a common occurrence. I would rather add Currie mini skids to the lower control arm brackets or with new brackets long before fixing that problem with an entirely new axle.

Okay. Any input on the gearing?
 
But I don't want to wait until it breaks. I go wheeling hundreds of miles from home, and being stranded with a broken CA bracket, or bent housing doesn't sound that appealing.

I understand that the weak point in the stock TJ axles is the shafts and outer components, but I guess the question is how often do people bend housings/Cs, and brackets on the stock axles?
Pretty much never, at least for 99.99% of us. Control arm brackets can get bent but they can get bent on Dana 60 axles too. I've yet to bend a TJ's axle housing, inner/outer C, etc. though my TJs have done trails that would scare 99% of people that offroad. Axle brackets yes, just not those other items. There's really no need to add gussets, axle sleeves, etc. at least not for the toughest stuff 35's are capable of.
 
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Pretty much never, at least for 99.99% of us. Control arm brackets can get bent but they can get bent on Dana 60 axles too. I've yet to bend a TJ's axle housing, inner/outer C, etc. though my TJs have done trails that would scare 99% of people that offroad. Axle brackets yes, just not those other items. There's really no need to add gussets, axle sleeves, etc. at least not for the toughest stuff 35's are capable of.

Ok. So my best bet would probably be to find and build a Rubi 44?
 
My LJ was a total, I put a lp 30 in it for now, found a hp30 cheap that was straight and since I am putting in new elockers, it was an easy decision to upgrade with revolution shafts and big brakes in the hp 30 at this point with 4.56’s. I have a hp44 from a 78 crewcab f250 that I could build, it’s just more work than I want to deal with.
 
Have you visited the Grimm Jeeper gear calculator? While 5.38's are the better choice it's up to you if the small difference is worth it.
My opinion is to stick with the Dana 30 and use the money saved to add a big brake kit to your build.
I just finished putting 5.13's in a HP Dana 30 for my LJ with plans for 35's. I thought about a Dana 44 but the Rubi axle wasn't a big enough upgrade and a Currie was overkill for my needs. Here's a screenshot of the difference between 5.13's (left) and 5.38's (right) with 35's.
Screenshot_20230320_161616_Chrome.jpg
 
I would build a Dana 44, truss, and gusset the inner knuckle if you are just running 35s. For 37s I would run a Rockjock44 etc. Anything bigger Dana 60. You can pickup a used Dana 44 inexpensively, I just don't think a Dana 30 is worth the time, effort, and money in the long run if you wheel seriously. My JK sport on 33" inner knuckle got bent during light wheeling. Hell some of them come out of spec from the factory.
 
I would build a Dana 44, truss, and gusset the inner knuckle if you are just running 35s. For 37s I would run a Rockjock44 etc. Anything bigger Dana 60. You can pickup a used Dana 44 inexpensively, I just don't think a Dana 30 is worth the time, effort, and money in the long run if you wheel seriously.
The TJ's Dana 30 and front Dana 44 are the exact same axle except for their center pumpkins and inner axle shafts. They use the exact same axle tubes, inner C, knuckle, u-joints, ball joints, and brakes. The TJ's Dana 30 only needs replacement chromoly axle shafts to be fully up to 35's and a front locker. It will hold up to serious rock crawling with 35's and a locker as mine did once I replaced its axle shafts.

And welcome to WTF, it's clear you have some good experience. :)
 
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The TJ's Dana 30 and front Dana 44 are the exact same axle except for their center pumpkins and inner axle shafts. They use the exact same axle tubes, inner C, knuckle, u-joints, ball joints, and brakes. The TJ's Dana 30 only needs replacement chromoly axle shafts to be fully up to 35's and a front locker. It will hold up to serious rock crawling with 35's and a locker as mine did once I replaced its axle shafts.

And welcome to WTF, it's clear you have some good experience. :)

We see things a little different. Maybe I should have mentioned more. The center section of the Dana 44 is slightly bigger because the Dana 44 has larger bearings and carrier. The Dana 30 only has 27 splines vs 30 on a Dana 44 Rubicon axles. Dana 44 axle size are bigger and has increased surface area because of the spline count. So you increased strength on both accounts. Plus a Dana 44 Rubicon already have a selectable locker and no need to upgrade axles.
 
The TJ's Dana 30 and front Dana 44 are the exact same axle except for their center pumpkins and inner axle shafts. They use the exact same axle tubes, inner C, knuckle, u-joints, ball joints, and brakes.

That is true of the OEM Dana 44, but not a Currie 44 which uses very different tubes and C's.