Novak Conversions Jeep Wrangler TJ radiator

Upgraded 27 spline Dana 35 axle shafts?

Researching the 27 spline axle shafts to increase strength without going full Super 35. What do you guys think?

Revolutions Discovery series almost gives no information about what their shafts are made of. This always bothers me.

The Yukon are 1541H, which is more flexible than 4340, and less brittle, which many claim makes them superior. 25% stronger than stock shafts AND you can use your stock shafts as backups on the trail. The splines are also rolled, which makes them 30% stronger and better than cut.

ECGS are 4340 Chromolly shafts. Strong, but more brittle in my understanding.

Alloy USA is saying there’s are 4340 and up to 40% stronger than OE

What do you guys know? Help me out here.

There's a whole bunch of confusion and one side of the equation going on so far. First, let's get apples to apples in perspective. 1541H is a case hardening alloy. 4340 is a through hardening alloy. They are not readily interchangeable due to the 35 axle having a bearing journal that the bearing rides on directly without adding a hardened race. For that application, the superior axle material is 1541H because it is plenty strong and because it is case hardening, you can bring the surface hardness up high enough to withstand bearing rollers riding on it. "IF" you try to bring 4340 up to the same hardness, it will be brittle because there is no ductility left at those levels of hardness. The 1541H will have a very high surface hardness with a softer core for a good level of ductility.

This is typical of what 4340 does when you try to use it for a bearing shaft and don't nail the heat treat.
23234.jpg

The very same thing that makes 4340 difficult to use for bearing shafts is what makes it a great material for non bearing shafts like the Dana 44 with Set 10 bearings. Since the hardness for a bearing journal isn't an issue, the heat treat can be brought up high enough that there is a lot of ductility left and a fairly high level of hardness throughout without it being brittle.

1541H Dana 35 shafts don't scare me, 4340 Dana 35 shafts scare me a lot.
 
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Thanks Blaine. I could have sworn I had read that very thing, pic included, but could not recall where or whom had written it. Appreciate the post and clarification.
 
Okay......so I keep going back and forth on the two. I have a 2000 TJ, 4.0, 5 speed. I already have an Eaton e-locker and Yukon 4.56 gears and 27 spline axles. I've been in Moab and going back next year. I might at some point do the Rubicon again with this Jeep this time. I don't get crazy on the skinny pedal, I like to slowly crawl over things, but don't spend a lot of times in the rocks. Which would be the best axle for me?
Thanks for your help.....
 
Thought this would be useful to you and others looking at axles,

https://www.dutchmanaxles.com/axle-tech
Thanks, that’s one of the main articles I had read last night. It lead me to think the 1541-H would be superior for the rear Dana 35, just like Blaine said. Now to figure out which one. Yukon and Rough Country both offer them, and perhaps others. My guess is they’re made in the same factory somewhere in China. I might make some calls
 
Anyone know what the Revolution 27 spline are made of? 1541 or 4340? Also, @AOR, would love to have you chime in on this thread
 
Thanks Blaine. I could have sworn I had read that very thing, pic included, but could not recall where or whom had written it. Appreciate the post and clarification.
The only reason 4340 Dana 35 shafts even exist is companies either grew weary of the education effort and lost sales, or they just pander to ignorance in that customers think 4340 is cool and strong so they have to have it. Similar to another company that advertises 4130 track bars. That is pure and total bullshit because 4340 is only marginally stronger unless you heat treat it. If you don't heat treat it, save yourself the expense and the penalty to the customer by using it. We both know why they do it and it isn't because it is a superior material, it because folks think 4130 is cool.
 
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Thanks, that’s one of the main articles I had read last night. It lead me to think the 1541-H would be superior for the rear Dana 35, just like Blaine said. Now to figure out which one. Yukon and Rough Country both offer them, and perhaps others. My guess is they’re made in the same factory somewhere in China. I might make some calls
I have a heat treater that I would trust to get 4340 hard enough to run a bearing on and then draw it back down for some ductility in the core. I wouldn't want to pay him for what that would take.
 
I have a heat treater that I would trust to get 4340 hard enough to run a bearing on and then draw it back down for some ductility in the core. I wouldn't want to pay him for what that would take.
So basically, are you saying that 4340 can be taken through a process that would make it a good rear axle shaft, but the time and effort is so costly it wouldn’t be worth it to the customer?
 
I still don't know which is the best one.....heat treated.....not heat treated.....made in USA? 4340 could be brittle but is not if not heat treated....1541-H is flexable......I'm going crazy.....I just want the right axle for what I'm doing.
 
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Thanks, that’s one of the main articles I had read last night. It lead me to think the 1541-H would be superior for the rear Dana 35, just like Blaine said. Now to figure out which one. Yukon and Rough Country both offer them, and perhaps others. My guess is they’re made in the same factory somewhere in China. I might make some calls
The ones I linked are from Revolution, for 88.75 per side.
 
I still don't know which is the best one.....heat treated.....not heat treated.....made in USA? 4340 could be brittle but is not if not heat treated....1541-H is flexable......I'm going crazy.....I just want the right axle for what I'm doing.
I won't speak for Blaine, but reading the link from Dutchman, and reading what Blaine wrote, the 1541H sounds like what you want.
 
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Okay......so I keep going back and forth on the two. I have a 2000 TJ, 4.0, 5 speed. I already have an Eaton e-locker and Yukon 4.56 gears and 27 spline axles. I've been in Moab and going back next year. I might at some point do the Rubicon again with this Jeep this time. I don't get crazy on the skinny pedal, I like to slowly crawl over things, but don't spend a lot of times in the rocks. Which would be the best axle for me?
Thanks for your help.....
 
I could be way off base hear. I thought Jerry said a good choice was the 4340 Revolution. Now is Blaine saying the 1541-H is better? I'm not going to heat treat anything. I'm just a "buy off the shelf" kinda guy.
 
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