Rubicon worth the extra money?

Interesting, out of curiosity why do you guys consider the HPD30 a better axle than an Dana 44? Just the added strength or is it factoring in cost too? What are some of the other advantages to the HPD30? They seem to suggest here the Dana 44 would still be stronger:
http://www.fourwheeler.com/how-to/tech-qa/1707-nuts-and-bolts-high-vs-low-pinion/

TLDR; this is the quote in the article (I don’t know enough to have an opinion.)
A stock high-pinion Dana 30 out of an XJ is going to be marginally stronger than an XJ low-pinion Dana 30, but a low-pinion Dana 44 is going to have much more strength than a high-pinion Dana 30 for several reasons. The larger, 8 1/2-inch-diameter ring gear of a Dana 44 is going to have much more tooth engagement (surface area) than the 7.2-inch-diameter gear of the Dana 30, and tooth contact is going to play more of a role in strength than which side of the gear the engine torque is being applied to. This is why larger-capacity axles (Dana 60, 14-bolt, and so on) have larger-diameter ring-and-pinions to match.

It is interesting hearing the different opinions. I think on my LJR search after reading this (and I guess what I already knew) is a non-rubicon clean low mileage non-rubicon LJ came up at the right price, it would be something for me to consider.
 
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Interesting, out of curiosity why do you guys consider the HPD30 a better axle than an Dana 44? Just the added strength or is it factoring in cost too? What are some of the other advantages to the HPD30? They seem to suggest here the Dana 44 would still be stronger:
http://www.fourwheeler.com/how-to/tech-qa/1707-nuts-and-bolts-high-vs-low-pinion/

TLDR; this is the quote in the article (I don’t know enough to have an opinion.)


It is interesting hearing the different opinions. I think on my LJR search after reading this (and I guess what I already knew) is a non-rubicon clean low mileage non-rubicon LJ came up at the right price, it would be something for me to consider.

For one, the higher clearance, but for two, the fact that the front Rubicon Dana 44 axle is standard cut gears:

Reverse Cut vs. Standard Cut
Perhaps the single most misunderstood axle term is reverse cut, often mistakenly referred to as reverse rotation. A reverse cut housing is not a standard cut housing turned upside down, it is a specially designed housing. The term "reverse cut" refers to the direction of the spiral cut in the ring gear, which is opposite that of a standard cut ring gear: Contrary to popular belief, it does not run backwards or in reverse. The principle behind a reverse cut is to strengthen the operation of the gear when it is used for a front driving axle application.

Hi-pinion or reverse-cut axles have also become very popular as rear driving axles in short wheelbase vehicles with suspension lifts because the higher pinion improves drive line angles so well.

Standard-cut axles are often used as the front driving axles because of clearance issues, gear ratio availability, cost, or suspension considerations. However comparable reverse-cut axles have the distinct advantage of overall ring and pinion gear strength.

Reverse-cut axles should be used in the rear when higher ground clearance, reduced drive shaft angles or short wheelbase are desirable issues. Reverse-cut rear axles should be avoided for heavy GVW vehicles or heavy highway towing.

The gear sets used in each type of axle are not interchangeable: Standard cut gears cannot be used in place of reverse cut, and vice versa. The housings, which have different lubrication passages, are also not interchangeable. However, differential cases (open, l/s, or locker) are compatible with both styles, as long as case spline count matches the axle shaft.

My understanding of this is that reverse cut gears are better for serious off-roading.
 
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Something to keep in mind is that many people are successfully running the Dana 30 and HP30 with 35s through Johnson Valley. Most of us are not running trails anywhere near that level of difficulty.
 
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I was only contrasting the TJ Rubicon Dana 44 which I don't feel is a true Dana 44. Since it shares the 27 spline outer shaft, bearings and u-joints with the Dana 30 I don't see it as that much better. The R&P will be stronger, but as I said, I only see that as a benefit if you are taking direct hits to the diff. A true Dana 44 is a different story and is superior to either of the TJ's axles.
 
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I was only contrasting the TJ Rubicon Dana 44 which I don't feel is a true Dana 44. Since it shares the 27 spline outer shaft, bearings and u-joints with the Dana 30 I don't see it as that much better. The R&P will be stronger, but as I said, I only see that as a benefit if you are taking direct hits to the diff. A true Dana 44 is a different story and is superior to either of the TJ's axles.
If you put chromoly shafts in a rubi the diff doesn't become a major weak point on the 44. Also even if you plan to replace the axles and tcase, if that's a down the road plane the rubi will still do better untill it happens than a standard tj. You will also make the extra Rubicon money back when you sell those parts used. I see buying a rubi as a no loss upgrade.

Rubicons also seem to more frequently come dual top also with more other options like the center console sub and AC, if you are into those things. (I know I am)


There must have been a time
when we could have said no.
 
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