Not saying I never buried my TJ in Mud but when I did and only once that I had to change all the outer bearings, seals and the Hypo Fluid with a week or to later - I learned my lesson.
Crown Automotive Supply Chromoly Axle Shafts
- Thread starter 13 OBA
- Start date
Why do you think after all these years, people have been incorrect about what causes that type of damage to a cromoly axle shaft when used in a Dana 35? Why does that damage not occur with 1541H axlesl shafts?
This right here is the technical explanation for why 1541H is the right choice. 1541H is essentially a medium carbon steel with some manganese added so that it can be hardened (that’s what the H on the end means). In the case of these axles, they are hardened on the surface to a very high hardness to act as the inner bearing race.
Anyone who specs a chrome molybdenum alloy for these shafts that act as a bearing race needs to take an introductory metallurgy class…
And to geek out a bit for purposes of education, here's Wikipedia's primer on the SAE steel classification system:
https://en.wikipedia.org/wiki/SAE_steel_grades
You'll find everything on that page to decode all five digits of 1 5 4 1 H, and after you decode it, @AndyG, the forum policy enforcer, will issue you your junior metallurgist certification.
https://en.wikipedia.org/wiki/SAE_steel_grades
You'll find everything on that page to decode all five digits of 1 5 4 1 H, and after you decode it, @AndyG, the forum policy enforcer, will issue you your junior metallurgist certification.
We don't need the technical side, it is easier to listen to idiots and let our gut change the metallurgy to force the shafts to work in our housings. For them that prefer a more truthful experience, the offering of 4000 series c-clip shafts by any company is a great litmus test to determine if that company knows what they are doing which allows one to ponder whether they are taking care of the customer or pandering to ignorance.
This right here is the technical explanation for why 1541H is the right choice. 1541H is essentially a medium carbon steel with some manganese added so that it can be hardened (that’s what the H on the end means). In the case of these axles, they are hardened on the surface to a very high hardness to act as the inner bearing race.
Anyone who specs a chrome molybdenum alloy for these shafts that act as a bearing race needs to take an introductory metallurgy class…
Occam's Razor. The simplest answer is most always correct. In this case, the reason you and so many others have so many miles on the stock shafts is because Dana knows they need a material that can be case hardened to create a hard surface for the Torrington style roller bearings to ride on. That also allows them to leave a more ductile core to handle torsional loads without fatigue failures.
You could have just started this by saying you were Canadian. We have a long history of dealing with folks from up there and across the board they are stubbornly willing to remain ignorant regardless of how sound the advice is.
And to geek out a bit for purposes of education, here's Wikipedia's primer on the SAE steel classification system:
https://en.wikipedia.org/wiki/SAE_steel_grades
You'll find everything on that page to decode all five digits of 1 5 4 1 H, and after you decode it, @AndyG, the forum policy enforcer, will issue you your junior metallurgist certification.
Maybe. Lotta paperwork involved.
Some of us learned it the hard way. Superior wanted a much higher strength u-joint with needle bearings in the caps. I did the one below and used the caps, needles, and seals from Spicer joints. They could buy them cheaper than they could buy the needles so they just robbed the caps and tossed the bodies in the scrap pile. The body is 4340 and it was a struggle to get the pins hard enough for the needles to ride on and then draw them back for some ductility in the core. As an engineer, you may appreciate the mitigation of the stress riser at the base of the pin to reduce cracks there.And to geek out a bit for purposes of education, here's Wikipedia's primer on the SAE steel classification system:
https://en.wikipedia.org/wiki/SAE_steel_grades
You'll find everything on that page to decode all five digits of 1 5 4 1 H, and after you decode it, @AndyG, the forum policy enforcer, will issue you your junior metallurgist certification.
You assumed the damage is from a seized bearing, but its actually because the surface isn't hard enough to hold up to bearings riding on the shaft. Like I said in the first response to your original post.
How dare you let the truth get in the way of going with your gut.
OP is apparently new here. Based on what I've seen on some other forums, I can forgive a guy for being skeptical of info on the internet. BUT (this is for you @13 OBA), you are getting advice from people actually involved in the design of a proven product (@mrblaine) and some others with credentials like engineering degrees (@sab) and a bunch of other folks with lots of practical experience. If you are willing listen, they will not steer you wrong.
I seem to be late to the Joust - I kinda over slept my afternoon nap ;o)
First of all I must thank all the Forum Members participating in my thread.
I do highly respect the Qualified Personal handing me advise and I am not dismissing it. We all can see the damage on the outer bearing surfaces of them Chromoly shafts; however, I saying it was not the fault of the shaft material, it started with a failed or failing bearing probably caused by leaking seals some time after a Mud Bath. Yes I agree that a 1541H Manganese Steel shaft will take more punishment under similar circumstances. With over 250,000 kilometers I have not damaged my stock axle shafts although I have muddy them once or twice but have always replaced the seals and bearing if required and changed out the Diff-Fluid shortly after a Muddy Encounter.
Given that the majority of TJ Forum Member recommend using 1541H Manganese Steel shafts over Chomoly in the Dana 35 rear End I will heed your advice and reluctantly purchase the 1541H shafts over the chromoly axles driven by 5:13 Gears and Lunch Box Lockers understanding that the 1541H shafts may not handle that style of Locker especially if I accidentally Buck it too Hard ;o(
I'm build for Mountian Climbing NOT Mud Bathing.
First of all I must thank all the Forum Members participating in my thread.
I do highly respect the Qualified Personal handing me advise and I am not dismissing it. We all can see the damage on the outer bearing surfaces of them Chromoly shafts; however, I saying it was not the fault of the shaft material, it started with a failed or failing bearing probably caused by leaking seals some time after a Mud Bath. Yes I agree that a 1541H Manganese Steel shaft will take more punishment under similar circumstances. With over 250,000 kilometers I have not damaged my stock axle shafts although I have muddy them once or twice but have always replaced the seals and bearing if required and changed out the Diff-Fluid shortly after a Muddy Encounter.
Given that the majority of TJ Forum Member recommend using 1541H Manganese Steel shafts over Chomoly in the Dana 35 rear End I will heed your advice and reluctantly purchase the 1541H shafts over the chromoly axles driven by 5:13 Gears and Lunch Box Lockers understanding that the 1541H shafts may not handle that style of Locker especially if I accidentally Buck it too Hard ;o(
I'm build for Mountian Climbing NOT Mud Bathing.
Observation does not equal causation. Just because it doesn't agree with your view of things does not change the truth. The reason the groove is worn in the 4xxx series shaft is because it can't be made hard enough to function as a bearing race or, if it is, it winds up being as brittle as glass and very easily broken which fully negates the use of the material. 4xxx series alloys are through hardening which means whatever temper and hardness you bring the core up to, that will be the same through the whole diameter of the shaft.
In order for an alloy to work in a c-clip axle where the bearing rollers ride on the shaft, you need to be able to bring the surface hardness up high enough to act as a bearing race and yet retain some ductility in the core. That is where the case hardening alloys come in, you can create a hard case (outer surface) around a softer core to get both. Same exact way gear steels work, hard wear surface with a ductile core for some minor flexibility in the teeth to prevent or mitigate shattering of the teeth.
Earned my degree in Metallurgical Engineering and Material Science just in time for a big downturn in those industries in the US. So pretty rusty on that in practice. @mrblaine is speaking truth. Steel is so useful because slight changes in the alloy can create wildly different properties for different uses.
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If you really really want chromoly axles, just swap in a dana 44
You don't have a cousin named Jerry do you?
Yup, if you use a non C-clip axle , you can save so much time defending , why you should use inappropriate axle shaft's ....
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