4340 Chromoly shafts in a D35...

dla

TJ Enthusiast
Supporting Member
Nov 25, 2017
177
SoCal
A little over two years ago I requested that my shafts be replaced with Yukon 4340's when I re-geared and added a Truetrac. Shortly after that is when I saw the post by @mrblaine showing the photo of the worn shaft where the bearing rides and his recommendation to never use 4340 shafts in a D35. I think his exact words words were along the lines of "I'd be very afraid...". During my prior research I had not found anything with regards to this problem.

Other than that first warning and now all the others repeating it every time the topic comes up I have not heard of or seen any other failures. There was no mention of failures or problems by my installer, Robert whom If I'm not mistaken works with or does work for Blaine from time to time.

At this point do I need to pull my shafts periodically and check for wear? Swap them out for 1541H shafts asap? Or run them and wait for them to possibly fail?

The Jeep is used around town and a weekend toy that gets pulled behind our motorhome and is used for desert exploration and moderate trails.
 

Jerry Bransford

TJ Guru
Supporting Member
Nov 9, 2015
9,957
Escondido California
The problem is the Dana 35's outer shaft bearings ride directly on the shaft, not on a bearing race like on a Dana 44 axle shaft uses. A 1541H shaft has its surface specially hardened as to stand up to the bearings constantly rolling on the surface. 4340 shafts have a different treatment process that doesn't harden the surface enough for the D35's type of bearings.
 
Reactions: Benjeepn
OP
dla

dla

TJ Enthusiast
Supporting Member
Nov 25, 2017
177
SoCal
The problem is the Dana 35's outer shaft bearings ride directly on the shaft, not on a bearing race like on a Dana 44 axle shaft uses. A 1541H shaft has its surface specially hardened as to stand up to the bearings constantly rolling on the surface. 4340 shafts have a different treatment process that doesn't harden the surface enough for the D35's type of bearings.
I'm aware of that now. Would not have gone with them if I knew that before.
 
Reactions: Jerry Bransford

Benjeepn

Member
Mar 8, 2019
30
AR, Walmart land
The problem is the Dana 35's outer shaft bearings ride directly on the shaft, not on a bearing race like on a Dana 44 axle shaft uses. A 1541H shaft has its surface specially hardened as to stand up to the bearings constantly rolling on the surface. 4340 shafts have a different treatment process that doesn't harden the surface enough for the D35's type of bearings.
So it uses a bearing like this? :oops:
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