JL Rubicon Axle Specs

[tiltz]

Has anybody torn down their axles yet?

I'm wanting to know the axle specs on the Rubicon.

Specifically:

1. Front and Rear Axle tube diameter and thickness
2. Axle shaft diameter and spline count
3. Ring and Pinion info (i know the ring diameters are posted, but curious about the thickness, tooth depth, etc)

I bent up my JK front axle even after trussing and adding inner tubes and also broke a front axle shaft (twice) so I am hoping that Jeep really built the front axle right for the JL.

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[K9Jeeper]

Has anybody torn down their axles yet?

I'm wanting to know the axle specs on the Rubicon.

Specifically:

1. Front and Rear Axle tube diameter and thickness
2. Axle shaft diameter and spline count
3. Ring and Pinion info (i know the ring diameters are posted, but curious about the thickness, tooth depth, etc)

I bent up my JK front axle even after trussing and adding inner tubes and also broke a front axle shaft (twice) so I am hoping that Jeep really built the front axle right for the JL.

I’m willing to bet you’re running at least 37s on that JK for that to happen. Or 35s and you wheel it extremely hard.

 

[tiltz]

Yes, it was a 2door on 37s and I put the Jeep to good use.

 

[K9Jeeper]

Yes, it was a 2door on 37s and I put the Jeep to good use.

Haha! Can’t fool a former JK owner that also wheeled hard and had plenty of problems in doing so.

 

[tiltz]

Here is the Jeep in question

 

[Tech Tim]

Has anybody torn down their axles yet?

I'm wanting to know the axle specs on the Rubicon.

Specifically:

1. Front and Rear Axle tube diameter and thickness
2. Axle shaft diameter and spline count
3. Ring and Pinion info (i know the ring diameters are posted, but curious about the thickness, tooth depth, etc)

I bent up my JK front axle even after trussing and adding inner tubes and also broke a front axle shaft (twice) so I am hoping that Jeep really built the front axle right for the JL.

The axle tube diameter went from 2.5" to 2.75" and the brackets are upgraded from .120" up to .200".

• Are the housings stronger, looks like it.
• Should you still look at trussing the housing if you're going to wheel 37s? Yes.

Rubicon shaft diameter and spline count hasn't changed from the JK, still 32 spline 1.366" on the rear and 1.30" - 30 spline inners on the front (32 spline outers).

The ring and pinions are similar, a little different tooth profile and RG dia. and some bearing changes.

We're working on an in-depth article covering the axle differences coming soon.

 

[Tyrantresister]

So how does the new JL Rubicon Axles compare to the J Recon that used the beefier J8 Axle hardware?

 

[tiltz]

Thanks for the info so the axle tube thickness is still .25?

Rear axle tube diameter still 3.25"?

 

[Tech Tim]

Still collecting data and don't want to drop too much info until the article is done.

Basically Dana & Jeep have done a good job making the axles better than the JK units, lots of cool changes. That said, they are still a production axle for a production car, so strength and longevity will depend on usage and abuse-age....

Northridge4x4 will be posting a copy of the article here on JLF when it's done.

 

[GinjaNinja]

The axle tube diameter went from 2.5" to 2.75" and the brackets are upgraded from .120" up to .200".

• Are the housings stronger, looks like it.
• Should you still look at trussing the housing if you're going to wheel 37s? Yes.

Rubicon shaft diameter and spline count hasn't changed from the JK, still 32 spline 1.366" on the rear and 1.30" - 30 spline inners on the front (32 spline outers).

The ring and pinions are similar, a little different tooth profile and RG dia. and some bearing changes.

We're working on an in-depth article covering the axle differences coming soon.

Hi Tim,

Any update on the in-depth article you were working on? I am curious whether these new Rubicon axles can handle heavy 35"-37" tires without mods...and if not, what mods would be required to strengthen the axles.

Cheers

 

[Tyrantresister]

So how does the new JL Rubicon Axles compare to the J Recon that used the beefier J8 Axle hardware?

Any info on this?

 

[Tech Tim]

Any update on the in-depth article you were working on? I am curious whether these new Rubicon axles can handle heavy 35"-37" tires without mods...and if not, what mods would be required to strengthen the axles.

In comparing the JL Rubicon axles to the JK Rubicon axles, the tubes are bigger and thicker, the suspension brackets are thicker, and front knuckle Cs are better. We do think these will hold up a better than the JK axles.

We're running 37s and just spend a week down at Easter Jeep Safari with no issues. Shad from Crawler Conceptz was running 40s on his JL and had no failures during the week.

Of course a lot will depend on the loose nut behind the wheel. An elegant driver can probably make a set of 40s live for a while, A thrash-wheeler will probably be breaking parts with 33s.

 

[GinjaNinja]

In comparing the JL Rubicon axles to the JK Rubicon axles, the tubes are bigger and thicker, the suspension brackets are thicker, and front knuckle Cs are better. We do think these will hold up a better than the JK axles.

We're running 37s and just spend a week down at Easter Jeep Safari with no issues. Shad from Crawler Conceptz was running 40s on his JL and had no failures during the week.

Of course a lot will depend on the loose nut behind the wheel. An elegant driver can probably make a set of 40s live for a while, A thrash-wheeler will probably be breaking parts with 33s.

Thanks Tim! I suppose we won't really know the limits of the axles until we get a lot more real world experiences. It is great to hear no issues so far with 37s and 40s at EJS this year! Still looking forward to your in depth article, I am sure it will be a great/informative read.

Cheers

 

[Tech Tim]

Here is Shad taking the "straight-shot" line on the Rocker Knocker on Pitchett Canyon trail.



Don't know how long those 44s will take that kind of abuse, but I'd wager that a JK rear 44 in that same scenario would've been hurt.

That JL has the EVO 2.5 Boost kit, modified flares and a little sheet metal trimming to fit the big 40" Nitto tires on it. No gears, no alloy axles, no extra fluff. Just a boost kit and some trimming.

 

[GinjaNinja]

Here is Shad taking the "straight-shot" line on the Rocker Knocker on Pitchett Canyon trail.



Don't know how long those 44s will take that kind of abuse, but I'd wager that a JK rear 44 in that same scenario would've been hurt.

That JL has the EVO 2.5 Boost kit, modified flares and a little sheet metal trimming to fit the big 40" Nitto tires on it. No gears, no alloy axles, no extra fluff. Just a boost kit and some trimming.

That is awesome! He was not taking it easy lol

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