Questions about axles

TJim

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Hey guys!

Just some random questions about Jeep axles.

1) Are the TJ front Dana 44s low pinion or high pinion? What about the JK front Dana 44s?

2) Are all the TJ Dana 35s low pinion? What about the rear Dana 44s?

3) As far as the rear axles go, there is no advantage for a high pinion vs a low pinion axle. Correct? (This is not similar to front axles)

4) ZJ, and XJs had HP Dana 30s. I know XJ HP 30 are a good swap for TJs (preferably not the ones with disconnects). Are ZJ HP 30 also a good bolt on axle? Or is there any difference?
 
1) Low pinion front 44s for TJs. JKs came with high pinion
2) Low pinion 35s and 44s for TJs
3) High pinion offers more ground clearance. Reverse driven gears which (arguably) are stronger
4) XJs HP30 are direct swaps. Disconnects can be used and there is also (arguably) an advantage to having the cast disconnect housing making the tube stronger. ZJs used low pinion dana and I dont recall them using a high pinion.
 
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1) Low pinion front 44s for TJs and JKs
2) Low pinion 35s and 44s for TJs
3) High pinion offers more ground clearance. Reverse driven gears which (arguably) are stronger
4) XJs HP30 are direct swaps. Disconnects can be used and there is also (arguably) an advantage to having the cast disconnect housing making the tube stronger. ZJs used low pinion dana and I dont recall them using a high pinion.
1) How come stock dana 44s are not HP? any ideas?

3) Reverse driven gears are stronger for rear axles too? I thought only for the front ones

4) ZJs used low pinions. Your are correct. I remembered wrong.
 
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1) How come stock dana 44s are not HP? any ideas?

3) Reverse driven gears are stronger for rear axles too? I thought only for the front ones

4) ZJs used low pinions. Your are correct. I remembered wrong.
My understanding was reverse driven gears in the rear are weeker while they are stronger in the front. But if im wrong someone shall chime in.
 
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My understanding was reverse driven gears in the rear are weeker while they are stronger in the front. But if im wrong someone shall chime in.
That is correct. It has to do with the side of the tooth that takes the load. One of the gearheads can explain it way better than me but that’s the general idea.
 
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3) Reverse driven gears are stronger for rear axles too? I thought only for the front ones
My understanding was reverse driven gears in the rear are weeker while they are stronger in the front. But if im wrong someone shall chime in.

My bad--I didnt see we were referring to rear. Its rare that you would find a reverse cut rear axle.
 
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1) Low pinion front 44s for TJs and JKs
2) Low pinion 35s and 44s for TJs
3) High pinion offers more ground clearance. Reverse driven gears which (arguably) are stronger
4) XJs HP30 are direct swaps. Disconnects can be used and there is also (arguably) an advantage to having the cast disconnect housing making the tube stronger. ZJs used low pinion dana and I dont recall them using a high pinion.
Jk front axles are hp in both 30 and 44 flavors.
 
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1) Low pinion front 44s for TJs and JKs
2) Low pinion 35s and 44s for TJs
3) High pinion offers more ground clearance. Reverse driven gears which (arguably) are stronger
4) XJs HP30 are direct swaps. Disconnects can be used and there is also (arguably) an advantage to having the cast disconnect housing making the tube stronger. ZJs used low pinion dana and I dont recall them using a high pinion.
1) Low pinion front 44 for TJ. High Pinion front 44 for JK.
 
Hey guys!

Just some random questions about Jeep axles.

1) Are the TJ front Dana 44s low pinion or high pinion? What about the JK front Dana 44s?

2) Are all the TJ Dana 35s low pinion? What about the rear Dana 44s?

3) As far as the rear axles go, there is no advantage for a high pinion vs a low pinion axle. Correct? (This is not similar to front axles)

4) ZJ, and XJs had HP Dana 30s. I know XJ HP 30 are a good swap for TJs (preferably not the ones with disconnects). Are ZJ HP 30 also a good bolt on axle? Or is there any difference?
IF you're rock crawling a high pinion rear is a great advantage. Keeps your driveline out of the rocks as well as the low pinion doesn't drag as much. Also better UJ angles for short driveline is another advantage.
 
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Swapping in JK axles seems like a lot of work for the axle your getting.
Depends on what you want. It’s a lot lighter than a Dana 60 and plenty strong in a TJ for a 37-40. I’m sure someone will jump in here to tell me why I’m wrong but a lot of people run them in TJ’s with great success.
 
Swapping in JK axles seems like a lot of work for the axle your getting.
The rear is easy.... the front is some work. Requires complete custom steering. The width change makes you start from scratch.
 
I have looked into this a few times and came to the same conclusion. It's just not worth the cost/complexity when weighed against the benefits. The amount of fabrication to make the steering and track bar work properly is no small task. Yes, the additional width makes outboarding or coil overs easier, I don't see much else past the gear sets and maybe brakes. But, it's not really enough axle or balljoint to run the vaunted 37s.

Time and time again, there are so many very capable builds on here and every offroad trail and park. You'll see many tj jeeps on 35s that just work. It's a proven recipe when done right and far less if any fabrication and custom design.
 
IMO if you are running 40" or smaller tires a properly built HP44 front axle and a HP60 semi-float rear axle is sufficient.

Yes using a HP axle in the rear makes that R&P about 20% weaker than running a LP axle in the rear.
When using a HP axle in the rear you are driving forward on the coast side of the ring gear. This is the weaker side of gear which is why a HP axle is desirable in the front because then you're on the drive side going forward.

A properly built HP44 has 3" axle tubes and either Dana 60 ball joints or old school Dana 44 ball joints as they are stronger than TJ/JK ones.

And then a semi-float HP60 rear running either Super60 R&P or a Dana 70 R&P using a Jantz 76 kit.
 
Does anybody offer this? My Currie HP44 uses standard TJ ball joints.
Not sure if anyone offers it new, but the old trucks that used Dana 44's had either heavier Balljoints or Kingpins. I've had a notion to put together an axle with Kingpins...Something like a JK center section with 3" tubes and old Chevy inner C's and knuckles. It would be a TON of work and probably require custom axle shafts...but it would be a pretty good axle when done, I think.
 
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