Originally Posted by Wrangler97-EEK
The joint usually fails which in turn causes damage to the ears on shafts.
That's not the usual order of breakage though some think it is. What really happens is the ears stretch and fail first from the u-joint pulling against them which releases the u-joint to spin free and collide with the ears. That is what causes the u-joint to break. The u-joint itself doesn't usually fail first.
If your friends are breaking "chromolly" axleshafts then they are likely off-brand imports or Mosers which don't have hardened ears. Good quality hardened alloy/chromolly shafts like the Evolution Series from Superior Axle don't break except very rarely like on extreme level trails like the Hammers in Johnson Valley. As I said, once I went with good quality Warn and Superior Axle hardened shafts, broken axle shafts became something of the past and I doubt you're seeing the level of difficulty there we commonly encounter here in our local desert rock crawling trails like out in Johnson Valley.
Once you get good quality hardened axle shafts like the Evolution Series from Superior and good u-joints installed, you won't have breakage issues again. These shafts hold up to the toughest trails in Johnson Valley where the final championship rock crawling events are held, plus the notoriously tough King of the Hammers series.
RCV's axles are excellent quality and they are strong, my entire point is that hardened chromolly shafts don't break "all the time" as you claimed above. Even your favored RCVs are made from chromolly steel, check their website.
And you are confused on chromolly axle shafts... you have said the "stock type chromolly shafts" and "chromoly axles that do break quite often" but the stock axle shafts are NOT chromolly. The stock shafts installed by Dana are carbon steel (not the same as chromolly) which ARE known to break. Even the RCV shafts you are pushing are made from chromolly. The shafts that break more easily which the factory installs are carbon steel, NOT chromolly or hardened alloy.
So, again, good quality aftermarket hardened alloy chromolly shafts do not "break all the time" and it doesn't take an RCV axle to prevent axle shaft breakages that are only common if you do the really tough trails and are still on the factory carbon steel