What are G2 Dana 44 rear axles made of?

Blue Patriot

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Anyone know what alloy these are made of? I’ve looked all over and can’t seem to find a definitive answer. I’ve heard everything from 4340 to not chromoly at all just an “alloy” stronger than stock. Any info would be greatly appreciated. Thanks!
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96-2045-1. Pretty much the same set but listed for disc brakes. Where did you happen to find that information? I’ve searched all over. Thanks appreciate the info!
I called them about a year ago for that particular product when I was looking for Dana 44 chromoly axle shafts when RGA was out of stock on theirs.

They should be the same for sure.
 
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That’s the impression I was under, but I don’t understand why. Same thing for the 4340 in the front.
I ran across a few technical papers on it some time back and being my typical goober self when it comes to that crap, I forgot to bookmark it. I do recall being fascinated when they went into the reasons why it makes more sense to use 4140 due to some different properties it has when heat treated correctly that make it more suitable for the wind up we get a lot of in rear axles. Essentially it used a whole bunch of engineer speak to say 4340 good, 4140 more gooder.
 
I ran across a few technical papers on it some time back and being my typical goober self when it comes to that crap, I forgot to bookmark it. I do recall being fascinated when they went into the reasons why it makes more sense to use 4140 due to some different properties it has when heat treated correctly that make it more suitable for the wind up we get a lot of in rear axles. Essentially it used a whole bunch of engineer speak to say 4340 good, 4140 more gooder.
I’ll try and find something similar. I find the technicals pretty interesting.

That makes me assume that 4140 handles twisting forces better than 4340, which then makes me wonder why 4340 is better for the front.

If all these shafts are 4140, is the main difference between the different companies the heat treating process? There’s a pretty wide range of costs for these shafts.
 
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I’ll try and find something similar. I find the technicals pretty interesting.

That makes me assume that 4140 handles twisting forces better than 4340, which then makes me wonder why 4340 is better for the front.

If all these shafts are 4140, is the main difference between the different companies the heat treating process? There’s a pretty wide range of costs for these shafts.
I think the higher strength of the 4340 comes into play for the yoke ears. If you find something, post it up so maybe I won't be dumb this time and forget to bookmark it. I've run across several things over the years I really regret not saving somehow. One of my favorites was test on air filters that a university did. Pretty interesting that a normal shop towel tossed over a flat filter still lets enough air through to keep an engine going with no loss in mileage.

Puts to rest a lot of the claims made by "high flow" filter companies.
 
I have also heard that 4140 is better suited than 4340 for rear axles, due to the idea that they have “more give” when twisting before breaking. The info about 4340 being better for the front because those axles have ears for the u-joints which we want to be stronger makes sense as well. Good stuff. Thanks guys
 
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I have also heard that 4140 is better suited than 4340 for rear axles, due to the idea that they have “more give” when twisting before breaking. The info about 4340 being better for the front because those axles have ears for the u-joints which we want to be stronger makes sense as well. Good stuff. Thanks guys
All that said, I'm not actually convinced that the companies are taking full advantage of the use of 4340 nowadays. The old Warn axles in the hub kits were tough as nails but if you blew one, there was nothing left. It just exploded. The new stuff by everyone, the yokes bend. That points to much lower levels of or different levels of heat treating and I'm not sure we aren't leaving a lot of performance on the table that we should be getting from 4340. In fact a lot of what I'm seeing on breaks is almost no HT or very little at the yoke ears.
 
Slightly off subject but how much of an advantage are chromoly axle shafts over OEM if you keep the spline count the same? I have ARBs that I do not want to replace. If I go to chromoly axle shafts do I just move the breaking point to my lockers?
 
Slightly off subject but how much of an advantage are chromoly axle shafts over OEM if you keep the spline count the same? I have ARBs that I do not want to replace. If I go to chromoly axle shafts do I just move the breaking point to my lockers?
I’ve heard everything from a 20% to a 40% increase in strength. To my understanding, chromoly axle shafts allow the shaft to twist rotationally much further before breaking plus they are harder to twist than OEM shafts.

Best quality shafts are Revolution USA made. Their discovery line are still very high quality. I have their discovery 27 spline shafts in my Dana 30.

One thing to keep in mind is that the 30 spline shafts still have the 27 spline stub which in my mind would be the weak point. Not the locker.

@mrblaine will have the best insight into where they are most likely to break or what would become the weakest link.
 
I’ve heard everything from a 20% to a 40% increase in strength. To my understanding, chromoly axle shafts allow the shaft to twist rotationally much further before breaking plus they are harder to twist than OEM shafts.

Best quality shafts are Revolution USA made. Their discovery line are still very high quality. I have their discovery 27 spline shafts in my Dana 30.

One thing to keep in mind is that the 30 spline shafts still have the 27 spline stub which in my mind would be the weak point. Not the locker.

@mrblaine will have the best insight into where they are most likely to break or what would become the weakest link.
Stub shafts are fairly confusing to most folks. We need to rely on observation and extrapolation some. Why do the 27 spline stubs have a very low as in statistically almost zero failure rate at the splines when used and installed properly?

We all know that the OEM stubs while serviceable at the smaller tire sizes are not anything special. The yokes break at the same rate as the inners, so why don't the stub shafts themselves break more often?

It has to do with the function of the stub shaft and what its job is. It holds the unit bearing halves together and it transfers torque to turn the tire after that or at the same time but what saves the stub is the large flat face shoulder that butts up to the back of the unit bearing. When the spindle nut is torqued properly to clamp the unit bearing together, the friction at those two faces works to greatly reduce the amount of torque load that the splines see.

If that weren't the case, all Rubicons with 30 spline inners would just twist off the stub shafts at an alarming rate.
 
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Stub shafts are fairly confusing to most folks. We need to rely on observation and extrapolation some. Why do the 27 spline stubs have a very low as in statistically almost zero failure rate at the splines when used and installed properly?

We all know that the OEM stubs while serviceable at the smaller tire sizes are not anything special. The yokes break at the same rate as the inners, so why don't the stub shafts themselves break more often?

It has to do with the function of the stub shaft and what its job is. It holds the unit bearing halves together and it transfers torque to turn the tire after that or at the same time but what saves the stub is the large flat face shoulder that butts up to the back of the unit bearing. When the spindle nut is torqued properly to clamp the unit bearing together, the friction at those two faces works to greatly reduce the amount of torque load that the splines see.

If that weren't the case, all Rubicons with 30 spline inners would just twist off the stub shafts at an alarming rate.
That makes a lot of sense now. Thanks for taking the time to explain that! I was completely unaware of the interaction between the unit bearing and the stub shaft. Good information to have.

How does that change with the use of something like Yukons 30 spline stub free spin kit?
 
Stub shafts are fairly confusing to most folks. We need to rely on observation and extrapolation some. Why do the 27 spline stubs have a very low as in statistically almost zero failure rate at the splines when used and installed properly?

We all know that the OEM stubs while serviceable at the smaller tire sizes are not anything special. The yokes break at the same rate as the inners, so why don't the stub shafts themselves break more often?

It has to do with the function of the stub shaft and what its job is. It holds the unit bearing halves together and it transfers torque to turn the tire after that or at the same time but what saves the stub is the large flat face shoulder that butts up to the back of the unit bearing. When the spindle nut is torqued properly to clamp the unit bearing together, the friction at those two faces works to greatly reduce the amount of torque load that the splines see.

If that weren't the case, all Rubicons with 30 spline inners would just twist off the stub shafts at an alarming rate.
Nice to know my recent failure is a statistical anomaly! G2 chromoly, FWIW.
 

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So with OEM spline ARBs do I get much of an advantage moving to chromoly shafts? I moved to 35s a few years ago and started doing harder trails (Moab Trifecta last October) and started thinking about more preventative maintenance. I have stock 30 front and 44 rear with 4.88s and ARBs. I only turn on the ARBs when I need to (and rear way more than both) and stay light on the gas. It's a manual so sometimes I need to hit it a little. Are the shafts worth the expense? Any expense is better than the bill to be towed out of Moab.