Exactly, because a TJR weighs a lot less than an F250 with a 400" engine. WHY would you want the weight of Dana 44 knuckles, brakes and bearings in a vehicle which does not need them?
Theories why the Rubicon went with D44s vs upgraded Dana 30/35?
- Thread starter Fouledplugs
- Start date
It used to be common in the 1960s to buy a Dodge Challenger with a Hemi and a Dana 60 center section, but the ends were not Dana 60 parts because a Challenger is way lighter than a loaded 1 ton truck.
It's essentially putting 1/2 ton parts in a 1/4 ton housing. Seems counter intuative. Would we classify this as a shortcut/half-a$$ing it?
Maybe thats one reason/theory why the engineers didnt go the route of upgraded Dana 35 shafts in the Rubicon, Im not sure what an automotive driveline engineer would think if you suggested 1/2 parts in a 1/4 ton housing. I think their quesiton would be, "Just go with the Dana 44, it meets the requierment of 1/2 parts and it includes a 1/2 ton housing." Makes sense in my head.
But you could be right about the weight of the TJ/LJ not needing the big tubes. Save that for the JK/JKU's. They came with the much bigger Dana 44 tubes and other Gen 2 parts.
What is the weight diff between the JK rubi and TJ Rubi?
Last edited:
I'd call it engineering. I've never heard of anyone driving a stock Rubicon breaking the axles.
Does the JK Rubicon weigh more? As it comes with the much bigger Dana 44's under it. Might be a hole in the theory, or they just went overkill with the axles under the JK Rubicon for no reason. As you pointed out, that would be a waste of material and money.
Last edited:
Unlike the JK Gen 2 Dana 44's, the TJ/JL Rubi 44's are built for the 31s that came on it.
I think its a recent change that Jeep has embraced people modifying their Wranglers. Heck, Mopar introduced crate axels and lift kits with the JK which supports upgrading and modifying a factory vehicle.
Correct me if I am wrong but this is a fairly new concept isnt it? I feel like when I was younger and the TJ was new, the auto manufacturers did not support modifications and dealers would not want to work on modified vehicles. Now it seems the opposite is true.
Last edited:
If this is true, why the big upgrade on the JK dana 44's? The pinion size is identical to the Dana 60...The tubes, shafts, and u-joints are all bigger...
Did they change direction or is there still a marketing conspiracy, or sales trick involved? Or did they change their direction towards the off roading market?
Seems like a lot of theories are out there yet some that counter them as well. Not trying to be malicious just sparking conversations.
And at the end of the thread, we would need a Dana engineer or Jeep engineer to explain. Even then , the explanation would likely go over my head.
Last edited:
I think you are really close, in my head atleast. With the 4.1 in the Rubicon's transfer case feeding more torque to the ring and pinion, you get the increased diameter ring and pinion from the Dana 44 center section.
The lower Rubicon 4.10 gears adding more torque mutiplication as well as the bigger 31 inch tires resulted in the bigger shafts.
I don't know what a Gen 1 and Gen 2 44 is. What are you referring to?
Both the TJ and JK Rubi 44 and Dana 30 share the same axle tube diameter and wall thickness. Lengths are different. Stub shafts are the same.
Which parts do you think are anything close to 1 ton specs?
Yes, but there is a considerable difference in success when you compare 5-6000 Currie products to 20 x that amount on the OEM side, considerable.
The only tube that is bigger is the rear axle tubes on the JK. The fronts are the same. The JK is considerably heavier than any TJ, the Unlimited is not even in the same ballpark.
I don't know the exact reasons why they made any switches.
I just know logistics, costs, roi, risk, failure rates, expected returns all factor in a decision like that.. especially in manufacturing. Also, supplier partnerships, material costs, etc...
Marketing initiatives, sales promotions, branding... that stuff probably has less weight in the decision making process.
Again.. i was not there, so wouldn't pretend to know exactly why... but business and financial analysis are major deciding factors.
I could be wrong, but Im not confused.
A 1350 u-joint is a 1 ton joint. The 1410 is also a 1 ton U-joint. The 1410 uses a wider body but the same-size caps as a 1350 joint. The 1350, it uses a wider body of the 1330 joint (3/4 ton) but with larger trunnions and caps...The front Gen2 Dana 44 uses a 1350 u-joint which is 1 ton spec.
I believe 1310's came in the TJ Dana 44..? @mrblaine
1310 on the left and 1350 is the second to the last. Thats a significant upgrade over a the Gen1 Dana 44 IMO.
The Gen2 Dana 44 pinion shaft is same size as a Dana 60 Pinion shaft at 1.625 inches. It also has a bigger ring gear measuring in at 8.8 versus 8.5 in the Gen1.
The front Gen2 is high pinion Dana 44 which increases the front R&G strength.
The Get 2 Dana 44 also uses bigger bearings in the differentials.
You are right on the Gen1 & Gen2 Front 44 using the same axle tube measurements. Did the TJ front 44 use 2.5 inch OD though? I imagine it's much smaller...
The rear Gen2 Dana 44 uses much bigger axle tubes measuring in at 3.15 inch OD. Not sure what the TJ Dana 44 rear measures. F&R still use .25 Wall
More info on the Gen1 and Gen2 Dana 44 axles can be found here:
https://www.dynatrac.com/blog/the-difference-between-new-generation-dana-44-axles-and-older-ones/
More info can be found here:
https://www.dynatrac.com/blog/the-difference-between-new-generation-dana-44-axles-and-older-ones/
The new Dana 44 tooth face is nearly a 1⁄2-inch larger which allows more tooth contact between the ring-and-pinion.
From left to right:
Gen 1 Dana 44: 8.5 inch ring gear, Gen 2 Dana 44: 8.8 inch ring gear, Dana 60: 9.75 inch ring gear.
Last edited:
An early article that dives into next gen Dana 44's written by the great Fred Williams.
http://www.fourwheeler.com/how-to/transmission-drivetrain/131-0906-rubicon-jk-dana-44-axles/
http://www.fourwheeler.com/how-to/transmission-drivetrain/131-0906-rubicon-jk-dana-44-axles/
Stubs look much different, and one uses the small 1310 u-joint, the JK Gen 2 stubs use a 1350 u-joint.
http://www.fourwheeler.com/how-to/t...n/129-0908-jeep-tj-jeep-jk-dana-44-axle-swap/
Stubs are the same relative to each axle family as per my comment above about helping Revolution make the JK joint axle kit for the TJ.
This will solve most of your dilemma.
2 of these are JK ball joints, 2 of them are TJ ball joints.
Similar threads
